Dissertations / Theses: 'M-PSI/02'

1

Mattioni, Stefania. "How input modality and visual experience affect the representation of categories in the brain." Doctoral thesis, Università degli studi di Trento, 2018. https://hdl.handle.net/11572/368170.

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The general aim of the present dissertation was to participate in the progress of our understanding of how sensory input and sensory experience impact on how the human brain implements categorical knowledge. The goal was twofold: (1) understand whether there are brain regions that encode information about different categories regardless of input modality and sensory experience (study 1); (2) deepen the investigation of the mechanisms that drive cross-modal and intra-modal plasticity following early blindness and the way they express during the processing of different categories presented as real-world sounds (study 2). To address these fundamental questions, we used fMRI to characterize the brain responses to different conceptual categories presented acoustically in sighted and early blind individuals, and visually in a separate sighted group. In study 1, we observed that the right posterior middle temporal gyrus (rpMTG) is the region that most reliably decoded categories and selectively correlated with conceptual models of our stimuli space independently of input modality and visual experience. However, this region maintains separate the representational format from the different modalities, revealing a multimodal rather than an amodal nature. In addition, we observed that VOTC showed distinct functional profiles according to the hemispheric side. The left VOTC showed an involvement in the acoustical categorization processing at the same degree in sighted and in blind individuals. We propose that this involvement might reflect an engagement of the left VOTC in more semantic/linguistic processing of the stimuli potentially supported by its enhanced connection with the language system. However, paralleling our observation in rpMTG, the representations from different modalities are maintained segregated in VOTC, showing little evidence for sensory-abstraction. On the other side, the right VOTC emerged as a sensory-related visual region in sighted with the ability to rewires itself toward acoustical stimulation in case of early visual deprivation. In study 2, we observed opposite effects of early visual deprivation on auditory decoding in occipital and temporal regions. While occipital regions contained more information about sound categories in the blind, the temporal cortex showed higher decoding in the sighted. This unbalance effect was stronger in the right hemisphere where we, also, observed a negative correlation between occipital and temporal decoding of sound categories in EB. These last results suggest that the intramodal and crossmodal reorganizations might be inter-connected. We therefore propose that the extension of non-visual functions in the occipital cortex of EB may trigger a network-level reorganization that reduce the computational load of the regions typically coding for the remaining senses due to the extension of such computation in occipital regions.

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2

Bruzzo, Angela <1979&gt. "Seizure prediction and control in epilepsy." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2008. http://amsdottorato.unibo.it/1010/1/Tesi_Bruzzo_Angela.pdf.

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The first part of my thesis presents an overview of the different approaches used in the past two decades in the attempt to forecast epileptic seizure on the basis of intracranial and scalp EEG. Past research could reveal some value of linear and nonlinear algorithms to detect EEG features changing over different phases of the epileptic cycle. However, their exact value for seizure prediction, in terms of sensitivity and specificity, is still discussed and has to be evaluated. In particular, the monitored EEG features may fluctuate with the vigilance state and lead to false alarms. Recently, such a dependency on vigilance states has been reported for some seizure prediction methods, suggesting a reduced reliability. An additional factor limiting application and validation of most seizure-prediction techniques is their computational load. For the first time, the reliability of permutation entropy [PE] was verified in seizure prediction on scalp EEG data, contemporarily controlling for its dependency on different vigilance states. PE was recently introduced as an extremely fast and robust complexity measure for chaotic time series and thus suitable for online application even in portable systems. The capability of PE to distinguish between preictal and interictal state has been demonstrated using Receiver Operating Characteristics (ROC) analysis. Correlation analysis was used to assess dependency of PE on vigilance states. Scalp EEG-Data from two right temporal epileptic lobe (RTLE) patients and from one patient with right frontal lobe epilepsy were analysed. The last patient was included only in the correlation analysis, since no datasets including seizures have been available for him. The ROC analysis showed a good separability of interictal and preictal phases for both RTLE patients, suggesting that PE could be sensitive to EEG modifications, not visible on visual inspection, that might occur well in advance respect to the EEG and clinical onset of seizures. However, the simultaneous assessment of the changes in vigilance showed that: a) all seizures occurred in association with the transition of vigilance states; b) PE was sensitive in detecting different vigilance states, independently of seizure occurrences. Due to the limitations of the datasets, these results cannot rule out the capability of PE to detect preictal states. However, the good separability between pre- and interictal phases might depend exclusively on the coincidence of epileptic seizure onset with a transition from a state of low vigilance to a state of increased vigilance. The finding of a dependency of PE on vigilance state is an original finding, not reported in literature, and suggesting the possibility to classify vigilance states by means of PE in an authomatic and objectic way. The second part of my thesis provides the description of a novel behavioral task based on motor imagery skills, firstly introduced (Bruzzo et al. 2007), in order to study mental simulation of biological and non-biological movement in paranoid schizophrenics (PS). Immediately after the presentation of a real movement, participants had to imagine or re-enact the very same movement. By key release and key press respectively, participants had to indicate when they started and ended the mental simulation or the re-enactment, making it feasible to measure the duration of the simulated or re-enacted movements. The proportional error between duration of the re-enacted/simulated movement and the template movement were compared between different conditions, as well as between PS and healthy subjects. Results revealed a double dissociation between the mechanisms of mental simulation involved in biological and non-biologial movement simulation. While for PS were found large errors for simulation of biological movements, while being more acurate than healthy subjects during simulation of non-biological movements. Healthy subjects showed the opposite relationship, making errors during simulation of non-biological movements, but being most accurate during simulation of non-biological movements. However, the good timing precision during re-enactment of the movements in all conditions and in both groups of participants suggests that perception, memory and attention, as well as motor control processes were not affected. Based upon a long history of literature reporting the existence of psychotic episodes in epileptic patients, a longitudinal study, using a slightly modified behavioral paradigm, was carried out with two RTLE patients, one patient with idiopathic generalized epilepsy and one patient with extratemporal lobe epilepsy. Results provide strong evidence for a possibility to predict upcoming seizures in RTLE patients behaviorally. In the last part of the thesis it has been validated a behavioural strategy based on neurobiofeedback training, to voluntarily control seizures and to reduce there frequency. Three epileptic patients were included in this study. The biofeedback was based on monitoring of slow cortical potentials (SCPs) extracted online from scalp EEG. Patients were trained to produce positive shifts of SCPs. After a training phase patients were monitored for 6 months in order to validate the ability of the learned strategy to reduce seizure frequency. Two of the three refractory epileptic patients recruited for this study showed improvements in self-management and reduction of ictal episodes, even six months after the last training session.

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3

Bruzzo, Angela <1979&gt. "Seizure prediction and control in epilepsy." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2008. http://amsdottorato.unibo.it/1010/.

Full text

Abstract:

The first part of my thesis presents an overview of the different approaches used in the past two decades in the attempt to forecast epileptic seizure on the basis of intracranial and scalp EEG. Past research could reveal some value of linear and nonlinear algorithms to detect EEG features changing over different phases of the epileptic cycle. However, their exact value for seizure prediction, in terms of sensitivity and specificity, is still discussed and has to be evaluated. In particular, the monitored EEG features may fluctuate with the vigilance state and lead to false alarms. Recently, such a dependency on vigilance states has been reported for some seizure prediction methods, suggesting a reduced reliability. An additional factor limiting application and validation of most seizure-prediction techniques is their computational load. For the first time, the reliability of permutation entropy [PE] was verified in seizure prediction on scalp EEG data, contemporarily controlling for its dependency on different vigilance states. PE was recently introduced as an extremely fast and robust complexity measure for chaotic time series and thus suitable for online application even in portable systems. The capability of PE to distinguish between preictal and interictal state has been demonstrated using Receiver Operating Characteristics (ROC) analysis. Correlation analysis was used to assess dependency of PE on vigilance states. Scalp EEG-Data from two right temporal epileptic lobe (RTLE) patients and from one patient with right frontal lobe epilepsy were analysed. The last patient was included only in the correlation analysis, since no datasets including seizures have been available for him. The ROC analysis showed a good separability of interictal and preictal phases for both RTLE patients, suggesting that PE could be sensitive to EEG modifications, not visible on visual inspection, that might occur well in advance respect to the EEG and clinical onset of seizures. However, the simultaneous assessment of the changes in vigilance showed that: a) all seizures occurred in association with the transition of vigilance states; b) PE was sensitive in detecting different vigilance states, independently of seizure occurrences. Due to the limitations of the datasets, these results cannot rule out the capability of PE to detect preictal states. However, the good separability between pre- and interictal phases might depend exclusively on the coincidence of epileptic seizure onset with a transition from a state of low vigilance to a state of increased vigilance. The finding of a dependency of PE on vigilance state is an original finding, not reported in literature, and suggesting the possibility to classify vigilance states by means of PE in an authomatic and objectic way. The second part of my thesis provides the description of a novel behavioral task based on motor imagery skills, firstly introduced (Bruzzo et al. 2007), in order to study mental simulation of biological and non-biological movement in paranoid schizophrenics (PS). Immediately after the presentation of a real movement, participants had to imagine or re-enact the very same movement. By key release and key press respectively, participants had to indicate when they started and ended the mental simulation or the re-enactment, making it feasible to measure the duration of the simulated or re-enacted movements. The proportional error between duration of the re-enacted/simulated movement and the template movement were compared between different conditions, as well as between PS and healthy subjects. Results revealed a double dissociation between the mechanisms of mental simulation involved in biological and non-biologial movement simulation. While for PS were found large errors for simulation of biological movements, while being more acurate than healthy subjects during simulation of non-biological movements. Healthy subjects showed the opposite relationship, making errors during simulation of non-biological movements, but being most accurate during simulation of non-biological movements. However, the good timing precision during re-enactment of the movements in all conditions and in both groups of participants suggests that perception, memory and attention, as well as motor control processes were not affected. Based upon a long history of literature reporting the existence of psychotic episodes in epileptic patients, a longitudinal study, using a slightly modified behavioral paradigm, was carried out with two RTLE patients, one patient with idiopathic generalized epilepsy and one patient with extratemporal lobe epilepsy. Results provide strong evidence for a possibility to predict upcoming seizures in RTLE patients behaviorally. In the last part of the thesis it has been validated a behavioural strategy based on neurobiofeedback training, to voluntarily control seizures and to reduce there frequency. Three epileptic patients were included in this study. The biofeedback was based on monitoring of slow cortical potentials (SCPs) extracted online from scalp EEG. Patients were trained to produce positive shifts of SCPs. After a training phase patients were monitored for 6 months in order to validate the ability of the learned strategy to reduce seizure frequency. Two of the three refractory epileptic patients recruited for this study showed improvements in self-management and reduction of ictal episodes, even six months after the last training session.

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4

Leo, Fabrizio <1978&gt. "Il ruolo del collicolo superiore nell'orientamento spaziale." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2009. http://amsdottorato.unibo.it/1423/1/leo_fabrizio_tesi.pdf.

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This thesis was aimed at verifying the role of the superior colliculus (SC) in human spatial orienting. To do so, subjects performed two experimental tasks that have been shown to involve SC’s activation in animals, that is a multisensory integration task (Experiment 1 and 2) and a visual target selection task (Experiment 3). To investigate this topic in humans, we took advantage of neurophysiological finding revealing that retinal S-cones do not send projections to the collicular and magnocellular pathway. In the Experiment 1, subjects performed a simple reaction-time task in which they were required to respond as quickly as possible to any sensory stimulus (visual, auditory or bimodal audio-visual). The visual stimulus could be an S-cone stimulus (invisible to the collicular and magnocellular pathway) or a long wavelength stimulus (visible to the SC). Results showed that when using S-cone stimuli, RTs distribution was simply explained by probability summation, indicating that the redundant auditory and visual channels are independent. Conversely, with red long-wavelength stimuli, visible to the SC, the RTs distribution was related to nonlinear neural summation, which constitutes evidence of integration of different sensory information. We also demonstrate that when AV stimuli were presented at fixation, so that the spatial orienting component of the task was reduced, neural summation was possible regardless of stimulus color. Together, these findings provide support for a pivotal role of the SC in mediating multisensory spatial integration in humans, when behavior involves spatial orienting responses. Since previous studies have shown an anatomical asymmetry of fibres projecting to the SC from the hemiretinas, the Experiment 2 was aimed at investigating temporo-nasal asymmetry in multisensory integration. To do so, subjects performed monocularly the same task shown in the Experiment 1. When spatially coincident audio-visual stimuli were visible to the SC (i.e. red stimuli), the RTE depended on a neural coactivation mechanism, suggesting an integration of multisensory information. When using stimuli invisible to the SC (i.e. purple stimuli), the RTE depended only on a simple statistical facilitation effect, in which the two sensory stimuli were processed by independent channels. Finally, we demonstrate that the multisensory integration effect was stronger for stimuli presented to the temporal hemifield than to the nasal hemifield. Taken together, these findings suggested that multisensory stimulation can be differentially effective depending on specific stimulus parameters. The Experiment 3 was aimed at verifying the role of the SC in target selection by using a color-oddity search task, comprising stimuli either visible or invisible to the collicular and magnocellular pathways. Subjects were required to make a saccade toward a target that could be presented alone or with three distractors of another color (either S-cone or long-wavelength). When using S-cone distractors, invisible to the SC, localization errors were similar to those observed in the distractor-free condition. Conversely, with long-wavelength distractors, visible to the SC, saccadic localization error and variability were significantly greater than in either the distractor-free condition or the S-cone distractors condition. Our results clearly indicate that the SC plays a direct role in visual target selection in humans. Overall, our results indicate that the SC plays an important role in mediating spatial orienting responses both when required covert (Experiments 1 and 2) and overt orienting (Experiment 3).

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5

Leo, Fabrizio <1978&gt. "Il ruolo del collicolo superiore nell'orientamento spaziale." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2009. http://amsdottorato.unibo.it/1423/.

Full text

Abstract:

This thesis was aimed at verifying the role of the superior colliculus (SC) in human spatial orienting. To do so, subjects performed two experimental tasks that have been shown to involve SC’s activation in animals, that is a multisensory integration task (Experiment 1 and 2) and a visual target selection task (Experiment 3). To investigate this topic in humans, we took advantage of neurophysiological finding revealing that retinal S-cones do not send projections to the collicular and magnocellular pathway. In the Experiment 1, subjects performed a simple reaction-time task in which they were required to respond as quickly as possible to any sensory stimulus (visual, auditory or bimodal audio-visual). The visual stimulus could be an S-cone stimulus (invisible to the collicular and magnocellular pathway) or a long wavelength stimulus (visible to the SC). Results showed that when using S-cone stimuli, RTs distribution was simply explained by probability summation, indicating that the redundant auditory and visual channels are independent. Conversely, with red long-wavelength stimuli, visible to the SC, the RTs distribution was related to nonlinear neural summation, which constitutes evidence of integration of different sensory information. We also demonstrate that when AV stimuli were presented at fixation, so that the spatial orienting component of the task was reduced, neural summation was possible regardless of stimulus color. Together, these findings provide support for a pivotal role of the SC in mediating multisensory spatial integration in humans, when behavior involves spatial orienting responses. Since previous studies have shown an anatomical asymmetry of fibres projecting to the SC from the hemiretinas, the Experiment 2 was aimed at investigating temporo-nasal asymmetry in multisensory integration. To do so, subjects performed monocularly the same task shown in the Experiment 1. When spatially coincident audio-visual stimuli were visible to the SC (i.e. red stimuli), the RTE depended on a neural coactivation mechanism, suggesting an integration of multisensory information. When using stimuli invisible to the SC (i.e. purple stimuli), the RTE depended only on a simple statistical facilitation effect, in which the two sensory stimuli were processed by independent channels. Finally, we demonstrate that the multisensory integration effect was stronger for stimuli presented to the temporal hemifield than to the nasal hemifield. Taken together, these findings suggested that multisensory stimulation can be differentially effective depending on specific stimulus parameters. The Experiment 3 was aimed at verifying the role of the SC in target selection by using a color-oddity search task, comprising stimuli either visible or invisible to the collicular and magnocellular pathways. Subjects were required to make a saccade toward a target that could be presented alone or with three distractors of another color (either S-cone or long-wavelength). When using S-cone distractors, invisible to the SC, localization errors were similar to those observed in the distractor-free condition. Conversely, with long-wavelength distractors, visible to the SC, saccadic localization error and variability were significantly greater than in either the distractor-free condition or the S-cone distractors condition. Our results clearly indicate that the SC plays a direct role in visual target selection in humans. Overall, our results indicate that the SC plays an important role in mediating spatial orienting responses both when required covert (Experiments 1 and 2) and overt orienting (Experiment 3).

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6

Passamonti, Claudia <1981&gt. "Effetti dell'integrazione visuo-acustica in pazienti con disturbo di campo visivo." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2009. http://amsdottorato.unibo.it/1430/1/passamonti_claudia_tesi.pdf.

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Human brain is provided with a flexible audio-visual system, which interprets and guides responses to external events according to spatial alignment, temporal synchronization and effectiveness of unimodal signals. The aim of the present thesis was to explore the possibility that such a system might represent the neural correlate of sensory compensation after a damage to one sensory pathway. To this purpose, three experimental studies have been conducted, which addressed the immediate, short-term and long-term effects of audio-visual integration on patients with Visual Field Defect (VFD). Experiment 1 investigated whether the integration of stimuli from different modalities (cross-modal) and from the same modality (within-modal) have a different, immediate effect on localization behaviour. Patients had to localize modality-specific stimuli (visual or auditory), cross-modal stimulus pairs (visual-auditory) and within-modal stimulus pairs (visual-visual). Results showed that cross-modal stimuli evoked a greater improvement than within modal stimuli, consistent with a Bayesian explanation. Moreover, even when visual processing was impaired, cross-modal stimuli improved performance in an optimal fashion. These findings support the hypothesis that the improvement derived from multisensory integration is not attributable to simple target redundancy, and prove that optimal integration of cross-modal signals occurs in processing stage which are not consciously accessible. Experiment 2 examined the possibility to induce a short term improvement of localization performance without an explicit knowledge of visual stimulus. Patients with VFD and patients with neglect had to localize weak sounds before and after a brief exposure to a passive cross-modal stimulation, which comprised spatially disparate or spatially coincident audio-visual stimuli. After exposure to spatially disparate stimuli in the affected field, only patients with neglect exhibited a shifts of auditory localization toward the visual attractor (the so called Ventriloquism After-Effect). In contrast, after adaptation to spatially coincident stimuli, both neglect and hemianopic patients exhibited a significant improvement of auditory localization, proving the occurrence of After Effect for multisensory enhancement. These results suggest the presence of two distinct recalibration mechanisms, each mediated by a different neural route: a geniculo-striate circuit and a colliculus-extrastriate circuit respectively. Finally, Experiment 3 verified whether a systematic audio-visual stimulation could exert a long-lasting effect on patients’ oculomotor behaviour. Eye movements responses during a visual search task and a reading task were studied before and after visual (control) or audio-visual (experimental) training, in a group of twelve patients with VFD and twelve controls subjects. Results showed that prior to treatment, patients’ performance was significantly different from that of controls in relation to fixations and saccade parameters; after audiovisual training, all patients reported an improvement in ocular exploration characterized by fewer fixations and refixations, quicker and larger saccades, and reduced scanpath length. Similarly, reading parameters were significantly affected by the training, with respect to specific impairments observed in left and right hemisphere–damaged patients. The present findings provide evidence that a systematic audio-visual stimulation may encourage a more organized pattern of visual exploration with long lasting effects. In conclusion, results from these studies clearly demonstrate that the beneficial effects of audio-visual integration can be retained in absence of explicit processing of visual stimulus. Surprisingly, an improvement of spatial orienting can be obtained not only when a on-line response is required, but also after either a brief or a long adaptation to audio-visual stimulus pairs, so suggesting the maintenance of mechanisms subserving cross-modal perceptual learning after a damage to geniculo-striate pathway. The colliculus-extrastriate pathway, which is spared in patients with VFD, seems to play a pivotal role in this sensory compensation.

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7

Passamonti, Claudia <1981&gt. "Effetti dell'integrazione visuo-acustica in pazienti con disturbo di campo visivo." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2009. http://amsdottorato.unibo.it/1430/.

Full text

Abstract:

Human brain is provided with a flexible audio-visual system, which interprets and guides responses to external events according to spatial alignment, temporal synchronization and effectiveness of unimodal signals. The aim of the present thesis was to explore the possibility that such a system might represent the neural correlate of sensory compensation after a damage to one sensory pathway. To this purpose, three experimental studies have been conducted, which addressed the immediate, short-term and long-term effects of audio-visual integration on patients with Visual Field Defect (VFD). Experiment 1 investigated whether the integration of stimuli from different modalities (cross-modal) and from the same modality (within-modal) have a different, immediate effect on localization behaviour. Patients had to localize modality-specific stimuli (visual or auditory), cross-modal stimulus pairs (visual-auditory) and within-modal stimulus pairs (visual-visual). Results showed that cross-modal stimuli evoked a greater improvement than within modal stimuli, consistent with a Bayesian explanation. Moreover, even when visual processing was impaired, cross-modal stimuli improved performance in an optimal fashion. These findings support the hypothesis that the improvement derived from multisensory integration is not attributable to simple target redundancy, and prove that optimal integration of cross-modal signals occurs in processing stage which are not consciously accessible. Experiment 2 examined the possibility to induce a short term improvement of localization performance without an explicit knowledge of visual stimulus. Patients with VFD and patients with neglect had to localize weak sounds before and after a brief exposure to a passive cross-modal stimulation, which comprised spatially disparate or spatially coincident audio-visual stimuli. After exposure to spatially disparate stimuli in the affected field, only patients with neglect exhibited a shifts of auditory localization toward the visual attractor (the so called Ventriloquism After-Effect). In contrast, after adaptation to spatially coincident stimuli, both neglect and hemianopic patients exhibited a significant improvement of auditory localization, proving the occurrence of After Effect for multisensory enhancement. These results suggest the presence of two distinct recalibration mechanisms, each mediated by a different neural route: a geniculo-striate circuit and a colliculus-extrastriate circuit respectively. Finally, Experiment 3 verified whether a systematic audio-visual stimulation could exert a long-lasting effect on patients’ oculomotor behaviour. Eye movements responses during a visual search task and a reading task were studied before and after visual (control) or audio-visual (experimental) training, in a group of twelve patients with VFD and twelve controls subjects. Results showed that prior to treatment, patients’ performance was significantly different from that of controls in relation to fixations and saccade parameters; after audiovisual training, all patients reported an improvement in ocular exploration characterized by fewer fixations and refixations, quicker and larger saccades, and reduced scanpath length. Similarly, reading parameters were significantly affected by the training, with respect to specific impairments observed in left and right hemisphere–damaged patients. The present findings provide evidence that a systematic audio-visual stimulation may encourage a more organized pattern of visual exploration with long lasting effects. In conclusion, results from these studies clearly demonstrate that the beneficial effects of audio-visual integration can be retained in absence of explicit processing of visual stimulus. Surprisingly, an improvement of spatial orienting can be obtained not only when a on-line response is required, but also after either a brief or a long adaptation to audio-visual stimulus pairs, so suggesting the maintenance of mechanisms subserving cross-modal perceptual learning after a damage to geniculo-striate pathway. The colliculus-extrastriate pathway, which is spared in patients with VFD, seems to play a pivotal role in this sensory compensation.

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8

Moretto, Giovanna <1979&gt. "Cognitive and affective processes in social actions and decisions." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2010. http://amsdottorato.unibo.it/3042/1/Giovanna.Moretto.tesi.pdf.

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The question of how we make, and how we should make judgments and decisions has occupied thinkers for many centuries. This thesis has the aim to add new evidences to clarify the brain’s mechanisms for decisions. The cognitive and the emotional processes of social actions and decisions are investigated with the aim to understand which brain areas are mostly involved. Four experimental studies are presented. A specific kind of population is involved in the first study (as well as in study III) concerning patients with lesion of ventromedial prefrontal cortex (vmPFC). This region is collocated in the ventral surface of frontal lobe, and it seems have an important role in social and moral decision in forecasting the negative emotional consequences of choice. In study I, it is examined whether emotions, specifically social emotions subserved by the vmPFC, affect people’s willingness to trust others. In study II is observed how incidental emotions could encourage trusting behaviour, especially when individuals are not aware of emotive stimulation. Study III has the aim to gather a direct psychophysiological evidence, both in healthy and neurologically impaired individuals, that emotions are crucially involved in shaping moral judgment, by preventing moral violations. Study IV explores how the moral meaning of a decision and its subsequent action can modulate the basic component of action such as sense of agency.

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9

Moretto, Giovanna <1979&gt. "Cognitive and affective processes in social actions and decisions." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2010. http://amsdottorato.unibo.it/3042/.

Full text

Abstract:

The question of how we make, and how we should make judgments and decisions has occupied thinkers for many centuries. This thesis has the aim to add new evidences to clarify the brain’s mechanisms for decisions. The cognitive and the emotional processes of social actions and decisions are investigated with the aim to understand which brain areas are mostly involved. Four experimental studies are presented. A specific kind of population is involved in the first study (as well as in study III) concerning patients with lesion of ventromedial prefrontal cortex (vmPFC). This region is collocated in the ventral surface of frontal lobe, and it seems have an important role in social and moral decision in forecasting the negative emotional consequences of choice. In study I, it is examined whether emotions, specifically social emotions subserved by the vmPFC, affect people’s willingness to trust others. In study II is observed how incidental emotions could encourage trusting behaviour, especially when individuals are not aware of emotive stimulation. Study III has the aim to gather a direct psychophysiological evidence, both in healthy and neurologically impaired individuals, that emotions are crucially involved in shaping moral judgment, by preventing moral violations. Study IV explores how the moral meaning of a decision and its subsequent action can modulate the basic component of action such as sense of agency.

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10

Gianelli, Claudia <1981&gt. "The language of action. How language translates the dynamics of our actions." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2010. http://amsdottorato.unibo.it/3050/1/claudia_gianelli_tesi.pdf.

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The general aim of the thesis was to investigate how and to what extent the characteristics of action organization are reflected in language, and how they influence language processing and understanding. Even though a huge amount of research has been devoted to the study of the motor effects of language, this issue is very debated in literature. Namely, the majority of the studies have focused on low-level motor effects such as effector-relatedness of action, whereas only a few studies have started to systematically investigate how specific aspects of action organization are encoded and reflected in language. After a review of previous studies on the relationship between language comprehension and action (chapter 1) and a critical discussion of some of them (chapter 2), the thesis is composed by three experimental chapters, each devoted to a specific aspect of action organization. Chapter 3 presents a study designed with the aim to disentangle the effective time course of the involvement of the motor system during language processing. Three kinematics experiments were designed in order to determine whether and, at which stage of motor planning and execution effector-related action verbs influence actions executed with either the same or a different effector. Results demonstrate that the goal of an action can be linguistically re-activated, producing a modulation of the motor response. In chapter 4, a second study investigates the interplay between the role of motor perspective (agent) and the organization of action in motor chains. More specifically, this kinematics study aims at deepening how goal can be translated in language, using as stimuli simple sentences composed by a pronoun (I, You, He/She) and a verb. Results showed that the perspective activated by the pronoun You reflects the motor pattern of the “agent” combined with the chain structure of the verb. These data confirm an early involvement of the motor system in language processing, suggesting that it is specifically modulated by the activation of the agent’s perspective. In chapter 5, the issue of perspective is specifically investigated, focusing on its role in language comprehension. In particular, this study aimed at determining how a specific perspective (induced for example by a personal pronoun) modulates motor behaviour during and after language processing. A classical compatibility effect (the Action-sentence compatibility effect) has been used to this aim. In three behavioural experiments the authors investigated how the ACE is modulated by taking first or third person perspective. Results from these experiments showed that the ACE effect occurs only when a first-person perspective is activated by the sentences used as stimuli. Overall, the data from this thesis contributed to disentangle several aspects of how action organization is translated in language, and then reactivated during language processing. This constitutes a new contribution to the field, adding lacking information on how specific aspects such as goal and perspective are linguistically described. In addition, these studies offer a new point of view to understand the functional implications of the involvement of the motor system during language comprehension, specifically from the point of view of our social interactions.

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11

Gianelli, Claudia <1981&gt. "The language of action. How language translates the dynamics of our actions." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2010. http://amsdottorato.unibo.it/3050/.

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The general aim of the thesis was to investigate how and to what extent the characteristics of action organization are reflected in language, and how they influence language processing and understanding. Even though a huge amount of research has been devoted to the study of the motor effects of language, this issue is very debated in literature. Namely, the majority of the studies have focused on low-level motor effects such as effector-relatedness of action, whereas only a few studies have started to systematically investigate how specific aspects of action organization are encoded and reflected in language. After a review of previous studies on the relationship between language comprehension and action (chapter 1) and a critical discussion of some of them (chapter 2), the thesis is composed by three experimental chapters, each devoted to a specific aspect of action organization. Chapter 3 presents a study designed with the aim to disentangle the effective time course of the involvement of the motor system during language processing. Three kinematics experiments were designed in order to determine whether and, at which stage of motor planning and execution effector-related action verbs influence actions executed with either the same or a different effector. Results demonstrate that the goal of an action can be linguistically re-activated, producing a modulation of the motor response. In chapter 4, a second study investigates the interplay between the role of motor perspective (agent) and the organization of action in motor chains. More specifically, this kinematics study aims at deepening how goal can be translated in language, using as stimuli simple sentences composed by a pronoun (I, You, He/She) and a verb. Results showed that the perspective activated by the pronoun You reflects the motor pattern of the “agent” combined with the chain structure of the verb. These data confirm an early involvement of the motor system in language processing, suggesting that it is specifically modulated by the activation of the agent’s perspective. In chapter 5, the issue of perspective is specifically investigated, focusing on its role in language comprehension. In particular, this study aimed at determining how a specific perspective (induced for example by a personal pronoun) modulates motor behaviour during and after language processing. A classical compatibility effect (the Action-sentence compatibility effect) has been used to this aim. In three behavioural experiments the authors investigated how the ACE is modulated by taking first or third person perspective. Results from these experiments showed that the ACE effect occurs only when a first-person perspective is activated by the sentences used as stimuli. Overall, the data from this thesis contributed to disentangle several aspects of how action organization is translated in language, and then reactivated during language processing. This constitutes a new contribution to the field, adding lacking information on how specific aspects such as goal and perspective are linguistically described. In addition, these studies offer a new point of view to understand the functional implications of the involvement of the motor system during language comprehension, specifically from the point of view of our social interactions.

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12

Bertini, Caterina <1981&gt. "Neural basis of visual deficits recovery: visual residual functions and multisensory integration." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2010. http://amsdottorato.unibo.it/3068/1/bertini_caterina_tesi.pdf.

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The ability of integrating into a unified percept sensory inputs deriving from different sensory modalities, but related to the same external event, is called multisensory integration and might represent an efficient mechanism of sensory compensation when a sensory modality is damaged by a cortical lesion. This hypothesis has been discussed in the present dissertation. Experiment 1 explored the role of superior colliculus (SC) in multisensory integration, testing patients with collicular lesions, patients with subcortical lesions not involving the SC and healthy control subjects in a multisensory task. The results revealed that patients with collicular lesions, paralleling the evidence of animal studies, demonstrated a loss of multisensory enhancement, in contrast with control subjects, providing the first lesional evidence in humans of the essential role of SC in mediating audio-visual integration. Experiment 2 investigated the role of cortex in mediating multisensory integrative effects, inducing virtual lesions by inhibitory theta-burst stimulation on temporo-parietal cortex, occipital cortex and posterior parietal cortex, demonstrating that only temporo-parietal cortex was causally involved in modulating the integration of audio-visual stimuli at the same spatial location. Given the involvement of the retino-colliculo-extrastriate pathway in mediating audio-visual integration, the functional sparing of this circuit in hemianopic patients is extremely relevant in the perspective of a multisensory-based approach to the recovery of unisensory defects. Experiment 3 demonstrated the spared functional activity of this circuit in a group of hemianopic patients, revealing the presence of implicit recognition of the fearful content of unseen visual stimuli (i.e. affective blindsight), an ability mediated by the retino-colliculo-extrastriate pathway and its connections with amygdala. Finally, Experiment 4 provided evidence that a systematic audio-visual stimulation is effective in inducing long-lasting clinical improvements in patients with visual field defect and revealed that the activity of the spared retino-colliculo-extrastriate pathway is responsible of the observed clinical amelioration, as suggested by the greater improvement observed in patients with cortical lesions limited to the occipital cortex, compared to patients with lesions extending to other cortical areas, found in tasks high demanding in terms of spatial orienting. Overall, the present results indicated that multisensory integration is mediated by the retino-colliculo-extrastriate pathway and that a systematic audio-visual stimulation, activating this spared neural circuit, is able to affect orientation towards the blind field in hemianopic patients and, therefore, might constitute an effective and innovative approach for the rehabilitation of unisensory visual impairments.

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13

Bertini, Caterina <1981&gt. "Neural basis of visual deficits recovery: visual residual functions and multisensory integration." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2010. http://amsdottorato.unibo.it/3068/.

Full text

Abstract:

The ability of integrating into a unified percept sensory inputs deriving from different sensory modalities, but related to the same external event, is called multisensory integration and might represent an efficient mechanism of sensory compensation when a sensory modality is damaged by a cortical lesion. This hypothesis has been discussed in the present dissertation. Experiment 1 explored the role of superior colliculus (SC) in multisensory integration, testing patients with collicular lesions, patients with subcortical lesions not involving the SC and healthy control subjects in a multisensory task. The results revealed that patients with collicular lesions, paralleling the evidence of animal studies, demonstrated a loss of multisensory enhancement, in contrast with control subjects, providing the first lesional evidence in humans of the essential role of SC in mediating audio-visual integration. Experiment 2 investigated the role of cortex in mediating multisensory integrative effects, inducing virtual lesions by inhibitory theta-burst stimulation on temporo-parietal cortex, occipital cortex and posterior parietal cortex, demonstrating that only temporo-parietal cortex was causally involved in modulating the integration of audio-visual stimuli at the same spatial location. Given the involvement of the retino-colliculo-extrastriate pathway in mediating audio-visual integration, the functional sparing of this circuit in hemianopic patients is extremely relevant in the perspective of a multisensory-based approach to the recovery of unisensory defects. Experiment 3 demonstrated the spared functional activity of this circuit in a group of hemianopic patients, revealing the presence of implicit recognition of the fearful content of unseen visual stimuli (i.e. affective blindsight), an ability mediated by the retino-colliculo-extrastriate pathway and its connections with amygdala. Finally, Experiment 4 provided evidence that a systematic audio-visual stimulation is effective in inducing long-lasting clinical improvements in patients with visual field defect and revealed that the activity of the spared retino-colliculo-extrastriate pathway is responsible of the observed clinical amelioration, as suggested by the greater improvement observed in patients with cortical lesions limited to the occipital cortex, compared to patients with lesions extending to other cortical areas, found in tasks high demanding in terms of spatial orienting. Overall, the present results indicated that multisensory integration is mediated by the retino-colliculo-extrastriate pathway and that a systematic audio-visual stimulation, activating this spared neural circuit, is able to affect orientation towards the blind field in hemianopic patients and, therefore, might constitute an effective and innovative approach for the rehabilitation of unisensory visual impairments.

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14

Cardini, Flavia <1980&gt. "Seeing and feeling the body." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2011. http://amsdottorato.unibo.it/4123/1/Cardini_Flavia_tesi.pdf.

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Recognizing one’s body as separate from the external world plays a crucial role in detecting external events, and thus in planning adequate reactions to them. In addition, recognizing one’s body as distinct from others’ bodies allows remapping the experiences of others onto one’s sensory system, providing improved social understanding. In line with these assumptions, two well-known multisensory mechanisms demonstrated modulations of somatosensation when viewing both one’s own and someone else’s body: the Visual Enhancement of Touch (VET) and the Visual Remapping of Touch (VRT) effects. Vision of the body, in the former, and vision of the body being touched, in the latter, enhance tactile processing. The present dissertation investigated the multisensory nature of these mechanisms and their neural bases. Further experiments compared these effects for viewing one’s own body or viewing another person’s body. These experiments showed important differences in multisensory processing for one’s own body, and for other bodies, and also highlighted interactions between VET and VRT effects. The present experimental evidence demonstrated that a multisensory representation of one’s body – underlie by a high order fronto-parietal network - sends rapid modulatory feedback to primary somatosensory cortex, thus functionally enhancing tactile processing. These effects were highly spatially-specific, and depended on current body position. In contrast, vision of another person’s body can drive mental representations able to modulate tactile perception without any spatial constraint. Finally, these modulatory effects seem sometimes to interact with high order information, such as emotional content of a face. This allows one’s somatosensory system to adequately modulate perception of external events on the body surface, as a function of its interaction with the emotional state expressed by another individual.

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15

Cardini, Flavia <1980&gt. "Seeing and feeling the body." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2011. http://amsdottorato.unibo.it/4123/.

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Abstract:

Recognizing one’s body as separate from the external world plays a crucial role in detecting external events, and thus in planning adequate reactions to them. In addition, recognizing one’s body as distinct from others’ bodies allows remapping the experiences of others onto one’s sensory system, providing improved social understanding. In line with these assumptions, two well-known multisensory mechanisms demonstrated modulations of somatosensation when viewing both one’s own and someone else’s body: the Visual Enhancement of Touch (VET) and the Visual Remapping of Touch (VRT) effects. Vision of the body, in the former, and vision of the body being touched, in the latter, enhance tactile processing. The present dissertation investigated the multisensory nature of these mechanisms and their neural bases. Further experiments compared these effects for viewing one’s own body or viewing another person’s body. These experiments showed important differences in multisensory processing for one’s own body, and for other bodies, and also highlighted interactions between VET and VRT effects. The present experimental evidence demonstrated that a multisensory representation of one’s body – underlie by a high order fronto-parietal network - sends rapid modulatory feedback to primary somatosensory cortex, thus functionally enhancing tactile processing. These effects were highly spatially-specific, and depended on current body position. In contrast, vision of another person’s body can drive mental representations able to modulate tactile perception without any spatial constraint. Finally, these modulatory effects seem sometimes to interact with high order information, such as emotional content of a face. This allows one’s somatosensory system to adequately modulate perception of external events on the body surface, as a function of its interaction with the emotional state expressed by another individual.

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16

Zamagni, Elisa <1983&gt. "Sviluppo, Basi Neurali e Patologie del Sé corporeo." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2012. http://amsdottorato.unibo.it/4426/1/Zamagni_Elisa_tesi.pdf.

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Il presente elaborato ha per oggetto la tematica del Sé, in particolar modo il Sé corporeo. Il primo capitolo illustrerà la cornice teorica degli studi sul riconoscimento del Sé corporeo, affrontando come avviene l’elaborazione del proprio corpo e del proprio volto rispetto alle parti corporee delle altre persone. Il secondo capitolo descriverà uno studio su soggetti sani che indaga l’eccitabilità della corteccia motoria nei processi di riconoscimento sé/altro. I risultati mostrano un incremento dell’eccitabilità corticospinale dell’emisfero destro in seguito alla presentazione di stimoli propri (mano e cellulare), a 600 e 900 ms dopo la presentazione dello stimolo, fornendo informazioni sulla specializzazione emisferica substrati neurali e sulla temporalità dei processi che sottendono all’elaborazione del sé. Il terzo capitolo indagherà il contributo del movimento nel riconoscimento del Sé corporeo in soggetti sani ed in pazienti con lesione cerebrale destra. Le evidenze mostrano come i pazienti, che avevano perso la facilitazione nell’elaborare le parti del proprio corpo statiche, presentano tale facilitazione in seguito alla presentazione di parti del proprio corpo in movimento. Il quarto capitolo si occuperà dello sviluppo del sé corporeo in bambini con sviluppo atipico, affetti da autismo, con riferimento al riconoscimento di posture emotive proprie ed altrui. Questo studio mostra come alcuni processi legati al sé possono essere preservati anche in bambini affetti da autismo. Inoltre i dati mostrano che il riconoscimento del sé corporeo è modulato dalle emozioni espresse dalle posture corporee sia in bambini con sviluppo tipico che in bambini affetti da autismo. Il quinto capitolo sarà dedicato al ruolo dei gesti nel riconoscimento del corpo proprio ed altrui. I dati di questo studio evidenziano come il contenuto comunicativo dei gesti possa facilitare l’elaborazione di parti del corpo altrui. Nella discussione generale i risultati dei diversi studi verranno considerati all’interno della loro cornice teorica.
The present study concerns the theme of the self, especially the bodily self. The first chapter will describe the theoretical framework of self-body recognition and the processing that allow us to distinguish one’s own body and face from body and face of someone else. The second chapter will investigate motor cortex excitability during self/other recognition processing in healthy subjects. The results show an increment of motor corticospinal excitability in the right hemisphere following the presentation of self stimuli (hand and phone), at 600 and 900 ms after stimulus presentation, providing evidences about neural substrates and temporal processes underlying self-body recognition. The third chapter will describe the role of the movement in self bodily recognition in healthy subjects and in patients with right brain damage. The evidences show that patients, who did not show the advantage in the implicit recognition of self static body parts , present this advantage in the implicit recognition of self dynamic body parts. The fourth chapter will focus on the development of the bodily self in children with typical development and in children with autism, with respect to the recognition of self/other emotional body postures. First, this study shows that the advantage in bodily self processing is preserved in children with autism. Second, emotional body postures modulate self and others body processing in typically developmental children as well as in children with autism. The fifth chapter will study the role of gesture in self/other bodily recognition processing, showing that the meaning of the gesture modulates the self/other processing. The processing of others’ hand is facilitated with meaningful compared to meaningless gestures. The overall significance of the results will be argued in the general discussion.

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17

Zamagni, Elisa <1983&gt. "Sviluppo, Basi Neurali e Patologie del Sé corporeo." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2012. http://amsdottorato.unibo.it/4426/.

Full text

Abstract:

Il presente elaborato ha per oggetto la tematica del Sé, in particolar modo il Sé corporeo. Il primo capitolo illustrerà la cornice teorica degli studi sul riconoscimento del Sé corporeo, affrontando come avviene l’elaborazione del proprio corpo e del proprio volto rispetto alle parti corporee delle altre persone. Il secondo capitolo descriverà uno studio su soggetti sani che indaga l’eccitabilità della corteccia motoria nei processi di riconoscimento sé/altro. I risultati mostrano un incremento dell’eccitabilità corticospinale dell’emisfero destro in seguito alla presentazione di stimoli propri (mano e cellulare), a 600 e 900 ms dopo la presentazione dello stimolo, fornendo informazioni sulla specializzazione emisferica substrati neurali e sulla temporalità dei processi che sottendono all’elaborazione del sé. Il terzo capitolo indagherà il contributo del movimento nel riconoscimento del Sé corporeo in soggetti sani ed in pazienti con lesione cerebrale destra. Le evidenze mostrano come i pazienti, che avevano perso la facilitazione nell’elaborare le parti del proprio corpo statiche, presentano tale facilitazione in seguito alla presentazione di parti del proprio corpo in movimento. Il quarto capitolo si occuperà dello sviluppo del sé corporeo in bambini con sviluppo atipico, affetti da autismo, con riferimento al riconoscimento di posture emotive proprie ed altrui. Questo studio mostra come alcuni processi legati al sé possono essere preservati anche in bambini affetti da autismo. Inoltre i dati mostrano che il riconoscimento del sé corporeo è modulato dalle emozioni espresse dalle posture corporee sia in bambini con sviluppo tipico che in bambini affetti da autismo. Il quinto capitolo sarà dedicato al ruolo dei gesti nel riconoscimento del corpo proprio ed altrui. I dati di questo studio evidenziano come il contenuto comunicativo dei gesti possa facilitare l’elaborazione di parti del corpo altrui. Nella discussione generale i risultati dei diversi studi verranno considerati all’interno della loro cornice teorica.
The present study concerns the theme of the self, especially the bodily self. The first chapter will describe the theoretical framework of self-body recognition and the processing that allow us to distinguish one’s own body and face from body and face of someone else. The second chapter will investigate motor cortex excitability during self/other recognition processing in healthy subjects. The results show an increment of motor corticospinal excitability in the right hemisphere following the presentation of self stimuli (hand and phone), at 600 and 900 ms after stimulus presentation, providing evidences about neural substrates and temporal processes underlying self-body recognition. The third chapter will describe the role of the movement in self bodily recognition in healthy subjects and in patients with right brain damage. The evidences show that patients, who did not show the advantage in the implicit recognition of self static body parts , present this advantage in the implicit recognition of self dynamic body parts. The fourth chapter will focus on the development of the bodily self in children with typical development and in children with autism, with respect to the recognition of self/other emotional body postures. First, this study shows that the advantage in bodily self processing is preserved in children with autism. Second, emotional body postures modulate self and others body processing in typically developmental children as well as in children with autism. The fifth chapter will study the role of gesture in self/other bodily recognition processing, showing that the meaning of the gesture modulates the self/other processing. The processing of others’ hand is facilitated with meaningful compared to meaningless gestures. The overall significance of the results will be argued in the general discussion.

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18

Magnani, Barbara <1982&gt. "The spatial representation of time." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2012. http://amsdottorato.unibo.it/4724/1/Magnani_Barbara_tesi.pdf.

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Numerosi studi mostrano che gli intervalli temporali sono rappresentati attraverso un codice spaziale che si estende da sinistra verso destra, dove gli intervalli brevi sono rappresentati a sinistra rispetto a quelli lunghi. Inoltre tale disposizione spaziale del tempo può essere influenzata dalla manipolazione dell’attenzione-spaziale. La presente tesi si inserisce nel dibattito attuale sulla relazione tra rappresentazione spaziale del tempo e attenzione-spaziale attraverso l’uso di una tecnica che modula l’attenzione-spaziale, ovvero, l’Adattamento Prismatico (AP). La prima parte è dedicata ai meccanismi sottostanti tale relazione. Abbiamo mostrato che spostando l’attenzione-spaziale con AP, verso un lato dello spazio, si ottiene una distorsione della rappresentazione di intervalli temporali, in accordo con il lato dello spostamento attenzionale. Questo avviene sia con stimoli visivi, sia con stimoli uditivi, nonostante la modalità uditiva non sia direttamente coinvolta nella procedura visuo-motoria di AP. Questo risultato ci ha suggerito che il codice spaziale utilizzato per rappresentare il tempo, è un meccanismo centrale che viene influenzato ad alti livelli della cognizione spaziale. La tesi prosegue con l’indagine delle aree corticali che mediano l’interazione spazio-tempo, attraverso metodi neuropsicologici, neurofisiologici e di neuroimmagine. In particolare abbiamo evidenziato che, le aree localizzate nell’emisfero destro, sono cruciali per l’elaborazione del tempo, mentre le aree localizzate nell’emisfero sinistro sono cruciali ai fini della procedura di AP e affinché AP abbia effetto sugli intervalli temporali. Infine, la tesi, è dedicata allo studio dei disturbi della rappresentazione spaziale del tempo. I risultati ci indicano che un deficit di attenzione-spaziale, dopo danno emisferico destro, provoca un deficit di rappresentazione spaziale del tempo, che si riflette negativamente sulla vita quotidiana dei pazienti. Particolarmente interessanti sono i risultati ottenuti mediante AP. Un trattamento con AP, efficace nel ridurre il deficit di attenzione-spaziale, riduce anche il deficit di rappresentazione spaziale del tempo, migliorando la qualità di vita dei pazienti.
Numerous studies showed that time intervals are represented via a spatial code ascending from left to right, where shorter intervals are represented to the left of longer intervals. There is also evidence that, this temporal-spatial line, can be manipulated by manipulating the spatial-attention direction. The present thesis contributes to the current debate on the relationship between spatial representation of time and spatial-attention by using a technique to modulate spatial-attention, i.e. Prismatic-Adaptation (PA). In a first part we wondered about the behavioral mechanisms of the spatial-attention and time interaction. We showed that a shift of spatial-attention toward a side of space by PA, induces a distortion of the representation of time stimuli according to the side of attentional manipulation. This is true for time stimuli presented in visual modality but also in auditory modality that is not directly involved in the visuo-motor procedure of PA. This results suggested that the spatial code used to represent time, is a very centralized representation that is affected by spatial operations at high levels of spatial cognition. We followed with the investigation of the cortical areas subtending the space-time interaction. With neuropsychological, neurophysiological and neuroimaging methods, we found that areas in the right hemisphere are selectively related to the pure processing of time, while areas in the left hemisphere are selectively related to the success of PA procedure and to the effects of PA on time. Finally, we focused on the study of the pathology of the spatial representation of time. We found that a spatial-attention deficit, following a right hemispheric stroke, induces a deficit in the spatial representation of time that reflects in patients’ daily life. Moreover we found that a PA treatment, effective in reducing the spatial-attention deficit, also reduces the spatial representation of time disorder, improving patients’ quality of life.

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19

Magnani, Barbara <1982&gt. "The spatial representation of time." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2012. http://amsdottorato.unibo.it/4724/.

Full text

Abstract:

Numerosi studi mostrano che gli intervalli temporali sono rappresentati attraverso un codice spaziale che si estende da sinistra verso destra, dove gli intervalli brevi sono rappresentati a sinistra rispetto a quelli lunghi. Inoltre tale disposizione spaziale del tempo può essere influenzata dalla manipolazione dell’attenzione-spaziale. La presente tesi si inserisce nel dibattito attuale sulla relazione tra rappresentazione spaziale del tempo e attenzione-spaziale attraverso l’uso di una tecnica che modula l’attenzione-spaziale, ovvero, l’Adattamento Prismatico (AP). La prima parte è dedicata ai meccanismi sottostanti tale relazione. Abbiamo mostrato che spostando l’attenzione-spaziale con AP, verso un lato dello spazio, si ottiene una distorsione della rappresentazione di intervalli temporali, in accordo con il lato dello spostamento attenzionale. Questo avviene sia con stimoli visivi, sia con stimoli uditivi, nonostante la modalità uditiva non sia direttamente coinvolta nella procedura visuo-motoria di AP. Questo risultato ci ha suggerito che il codice spaziale utilizzato per rappresentare il tempo, è un meccanismo centrale che viene influenzato ad alti livelli della cognizione spaziale. La tesi prosegue con l’indagine delle aree corticali che mediano l’interazione spazio-tempo, attraverso metodi neuropsicologici, neurofisiologici e di neuroimmagine. In particolare abbiamo evidenziato che, le aree localizzate nell’emisfero destro, sono cruciali per l’elaborazione del tempo, mentre le aree localizzate nell’emisfero sinistro sono cruciali ai fini della procedura di AP e affinché AP abbia effetto sugli intervalli temporali. Infine, la tesi, è dedicata allo studio dei disturbi della rappresentazione spaziale del tempo. I risultati ci indicano che un deficit di attenzione-spaziale, dopo danno emisferico destro, provoca un deficit di rappresentazione spaziale del tempo, che si riflette negativamente sulla vita quotidiana dei pazienti. Particolarmente interessanti sono i risultati ottenuti mediante AP. Un trattamento con AP, efficace nel ridurre il deficit di attenzione-spaziale, riduce anche il deficit di rappresentazione spaziale del tempo, migliorando la qualità di vita dei pazienti.
Numerous studies showed that time intervals are represented via a spatial code ascending from left to right, where shorter intervals are represented to the left of longer intervals. There is also evidence that, this temporal-spatial line, can be manipulated by manipulating the spatial-attention direction. The present thesis contributes to the current debate on the relationship between spatial representation of time and spatial-attention by using a technique to modulate spatial-attention, i.e. Prismatic-Adaptation (PA). In a first part we wondered about the behavioral mechanisms of the spatial-attention and time interaction. We showed that a shift of spatial-attention toward a side of space by PA, induces a distortion of the representation of time stimuli according to the side of attentional manipulation. This is true for time stimuli presented in visual modality but also in auditory modality that is not directly involved in the visuo-motor procedure of PA. This results suggested that the spatial code used to represent time, is a very centralized representation that is affected by spatial operations at high levels of spatial cognition. We followed with the investigation of the cortical areas subtending the space-time interaction. With neuropsychological, neurophysiological and neuroimaging methods, we found that areas in the right hemisphere are selectively related to the pure processing of time, while areas in the left hemisphere are selectively related to the success of PA procedure and to the effects of PA on time. Finally, we focused on the study of the pathology of the spatial representation of time. We found that a spatial-attention deficit, following a right hemispheric stroke, induces a deficit in the spatial representation of time that reflects in patients’ daily life. Moreover we found that a PA treatment, effective in reducing the spatial-attention deficit, also reduces the spatial representation of time disorder, improving patients’ quality of life.

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20

Jacquet, Pierre Olivier <1980&gt. "Social learning and action understanding in human observers: contributions of sensori-motor constraints and prior information." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2012. http://amsdottorato.unibo.it/5073/1/Jacquet_Pierre_Olivier_Tesi.pdf.

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Abstract:

The aim of this thesis was to investigate the respective contribution of prior information and sensorimotor constraints to action understanding, and to estimate their consequences on the evolution of human social learning. Even though a huge amount of literature is dedicated to the study of action understanding and its role in social learning, these issues are still largely debated. Here, I critically describe two main perspectives. The first perspective interprets faithful social learning as an outcome of a fine-grained representation of others’ actions and intentions that requires sophisticated socio-cognitive skills. In contrast, the second perspective highlights the role of simpler decision heuristics, the recruitment of which is determined by individual and ecological constraints. The present thesis aims to show, through four experimental works, that these two contributions are not mutually exclusive. A first study investigates the role of the inferior frontal cortex (IFC), the anterior intraparietal area (AIP) and the primary somatosensory cortex (S1) in the recognition of other people’s actions, using a transcranial magnetic stimulation adaptation paradigm (TMSA). The second work studies whether, and how, higher-order and lower-order prior information (acquired from the probabilistic sampling of past events vs. derived from an estimation of biomechanical constraints of observed actions) interacts during the prediction of other people’s intentions. Using a single-pulse TMS procedure, the third study investigates whether the interaction between these two classes of priors modulates the motor system activity. The fourth study tests the extent to which behavioral and ecological constraints influence the emergence of faithful social learning strategies at a population level. The collected data contribute to elucidate how higher-order and lower-order prior expectations interact during action prediction, and clarify the neural mechanisms underlying such interaction. Finally, these works provide/open promising perspectives for a better understanding of social learning, with possible extensions to animal models.
L’obbiettivo della presente tesi consiste nell’esaminare il contributo dell’informazione a priori e dei vincoli sensorimotori per la comprensione delle azioni altrui, e nello stimare le loro conseguenze sull’evoluzione del apprendimento sociale. Nonostante allo studio della comprensione dell’azione e al suo ruolo nell’ apprendimento sociale sia dedicata un’ampia letteratura, queste problematiche rimangono molto dibattute. Nella tesi illustro due prospettive. La prima interpreta l’apprendimento sociale di alto livello come il prodotto di una rappresentazione a grana fine delle azioni e intenzioni altrui che richiede sofisticate abilità socio-cognitive. La seconda prospettiva sottolinea il ruolo di euristiche decisionali più semplici, il cui reclutamento è determinato da vincoli individuali ed ecologici. Attraverso quattro lavori sperimentali, viene dimostrato che questi due contributi non sono mutuamente esclusivi. Un primo studio esamina il ruolo della corteccia frontale inferiore (IFC), dell’area intraparietale anteriore (AIP) e della corteccia somatosensoriale primaria (S1) nel riconoscimento delle azioni, usando un paradigma di transcranial magnetic stimulation adaptation (TMSA). Il secondo lavoro studia se, e come, informazioni a priori di ordine superiore (acquisite dal campionamento probabilistico di eventi passati) e inferiore (derivate dalla stima degli impedimenti biomecanicci legati alle azione osservate) interagiscono durante la predizione delle intenzioni altrui. Usando una procedura di single-pulse TMS, il terzo lavoro esamina se l’interazione fra queste due classi di informazioni a priori modula l’attività del sistema motorio. Il quarto studio testa l’ampiezza con cui vincoli comportamentali ed ecologici possono influenzare, a livello popolazionale, la comparsa di strategie d’apprendimento sociale di grana fine. I dati raccolti contribuiscono a delucidare come le aspettative a priori di ordine superiore e inferiore interagiscano durante la predizione dell’azione, e chiarificano i meccanismi neurali sottostanti questa interazione. Infine, questi lavori aprono prospettive promettenti per una migliore comprensione dell’apprendimento sociale umano, con possibile estensioni ai modelli animali.

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21

Jacquet, Pierre Olivier <1980&gt. "Social learning and action understanding in human observers: contributions of sensori-motor constraints and prior information." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2012. http://amsdottorato.unibo.it/5073/.

Full text

Abstract:

The aim of this thesis was to investigate the respective contribution of prior information and sensorimotor constraints to action understanding, and to estimate their consequences on the evolution of human social learning. Even though a huge amount of literature is dedicated to the study of action understanding and its role in social learning, these issues are still largely debated. Here, I critically describe two main perspectives. The first perspective interprets faithful social learning as an outcome of a fine-grained representation of others’ actions and intentions that requires sophisticated socio-cognitive skills. In contrast, the second perspective highlights the role of simpler decision heuristics, the recruitment of which is determined by individual and ecological constraints. The present thesis aims to show, through four experimental works, that these two contributions are not mutually exclusive. A first study investigates the role of the inferior frontal cortex (IFC), the anterior intraparietal area (AIP) and the primary somatosensory cortex (S1) in the recognition of other people’s actions, using a transcranial magnetic stimulation adaptation paradigm (TMSA). The second work studies whether, and how, higher-order and lower-order prior information (acquired from the probabilistic sampling of past events vs. derived from an estimation of biomechanical constraints of observed actions) interacts during the prediction of other people’s intentions. Using a single-pulse TMS procedure, the third study investigates whether the interaction between these two classes of priors modulates the motor system activity. The fourth study tests the extent to which behavioral and ecological constraints influence the emergence of faithful social learning strategies at a population level. The collected data contribute to elucidate how higher-order and lower-order prior expectations interact during action prediction, and clarify the neural mechanisms underlying such interaction. Finally, these works provide/open promising perspectives for a better understanding of social learning, with possible extensions to animal models.
L’obbiettivo della presente tesi consiste nell’esaminare il contributo dell’informazione a priori e dei vincoli sensorimotori per la comprensione delle azioni altrui, e nello stimare le loro conseguenze sull’evoluzione del apprendimento sociale. Nonostante allo studio della comprensione dell’azione e al suo ruolo nell’ apprendimento sociale sia dedicata un’ampia letteratura, queste problematiche rimangono molto dibattute. Nella tesi illustro due prospettive. La prima interpreta l’apprendimento sociale di alto livello come il prodotto di una rappresentazione a grana fine delle azioni e intenzioni altrui che richiede sofisticate abilità socio-cognitive. La seconda prospettiva sottolinea il ruolo di euristiche decisionali più semplici, il cui reclutamento è determinato da vincoli individuali ed ecologici. Attraverso quattro lavori sperimentali, viene dimostrato che questi due contributi non sono mutuamente esclusivi. Un primo studio esamina il ruolo della corteccia frontale inferiore (IFC), dell’area intraparietale anteriore (AIP) e della corteccia somatosensoriale primaria (S1) nel riconoscimento delle azioni, usando un paradigma di transcranial magnetic stimulation adaptation (TMSA). Il secondo lavoro studia se, e come, informazioni a priori di ordine superiore (acquisite dal campionamento probabilistico di eventi passati) e inferiore (derivate dalla stima degli impedimenti biomecanicci legati alle azione osservate) interagiscono durante la predizione delle intenzioni altrui. Usando una procedura di single-pulse TMS, il terzo lavoro esamina se l’interazione fra queste due classi di informazioni a priori modula l’attività del sistema motorio. Il quarto studio testa l’ampiezza con cui vincoli comportamentali ed ecologici possono influenzare, a livello popolazionale, la comparsa di strategie d’apprendimento sociale di grana fine. I dati raccolti contribuiscono a delucidare come le aspettative a priori di ordine superiore e inferiore interagiscano durante la predizione dell’azione, e chiarificano i meccanismi neurali sottostanti questa interazione. Infine, questi lavori aprono prospettive promettenti per una migliore comprensione dell’apprendimento sociale umano, con possibile estensioni ai modelli animali.

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22

Mengarelli, Flavia <1980&gt. "Integration of cognitive and affective processes in perception and decision-making." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2012. http://amsdottorato.unibo.it/5074/1/Mengarelli_Flavia_Tesi.pdf.

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Abstract:

The relationship between emotion and cognition is a topic that raises great interest in research. Recently, a view of these two processes as interactive and mutually influencing each other has become predominant. This dissertation investigates the reciprocal influences of emotion and cognition, both at behavioral and neural level, in two specific fields, such as attention and decision-making. Experimental evidence on how emotional responses may affect perceptual and attentional processes has been reported. In addition, the impact of three factors, such as personality traits, motivational needs and social context, in modulating the influence that emotion exerts on perception and attention has been investigated. Moreover, the influence of cognition on emotional responses in decision-making has been demonstrated. The current experimental evidence showed that cognitive brain regions such as the dorsolateral prefrontal cortex are causally implicated in regulation of emotional responses and that this has an effect at both pre and post decisional stages. There are two main conclusions of this dissertation: firstly, emotion exerts a strong influence on perceptual and attentional processes but, at the same time, this influence may also be modulated by other factors internal and external to the individuals. Secondly, cognitive processes may modulate emotional prepotent responses, by serving a regulative function critical to driving and shaping human behavior in line with current goals.
La relazione tra emozione e cognizione è un argomento che ha suscitato grande interesse nella ricerca. Recentemente, una visione interattiva e di mutua influenza fra questi due processi è diventata predominante. Il presente lavoro di tesi indaga le influenze reciproche di emozione e cognizione, sia a livello comportamentale che neurale, in due specifici settori, quali l'attenzione e i processi decisionali. Nella prima parte, il lavoro presenta evidenze sperimentali di come le emozioni possano influenzare processi cognitivi come quelli percettivi ed attentivi. Allo stesso tempo aggiunge su come alcuni particolare fattori, come la personalità, le esigenze motivazionali del soggetto e il contesto sociale, possano modulare l’influenza che le emozioni esercitano sui processi cognitive in questione. Nella seconda parte é stato investigato l’influsso della cognizione sulle risposte emotive, in particolare durante i processi decisionali. I risultati degli esperimenti mostrano che regioni cerebrali cognitive, come la corteccia prefrontale dorsolaterale, sono implicate in modo causale nella regolazione e nel controllo di risposte emotive automatiche e che cio’ ha un effetto sia in fasi pre-decisionali (formazione della decisione) sia in fasi post-decisionali (cambiamento di preferenze). Due sono le principali conclusioni di questa tesi: in primo luogo, è stato mostrato che l'emozione esercita una forte influenza sui processi percettivi e attentivi, ma che, allo stesso tempo, questa influenza può essere modulata da altri fattori interni ed esterni agli individui. In secondo luogo, è stato mostrato che i processi cognitivi interagiscono con quelli emotivi svolgendo un funzione regolatrice fondamentale per guidare e plasmare il comportamento umano in linea con gli obiettivi correnti degli individui.

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23

Mengarelli, Flavia <1980&gt. "Integration of cognitive and affective processes in perception and decision-making." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2012. http://amsdottorato.unibo.it/5074/.

Full text

Abstract:

The relationship between emotion and cognition is a topic that raises great interest in research. Recently, a view of these two processes as interactive and mutually influencing each other has become predominant. This dissertation investigates the reciprocal influences of emotion and cognition, both at behavioral and neural level, in two specific fields, such as attention and decision-making. Experimental evidence on how emotional responses may affect perceptual and attentional processes has been reported. In addition, the impact of three factors, such as personality traits, motivational needs and social context, in modulating the influence that emotion exerts on perception and attention has been investigated. Moreover, the influence of cognition on emotional responses in decision-making has been demonstrated. The current experimental evidence showed that cognitive brain regions such as the dorsolateral prefrontal cortex are causally implicated in regulation of emotional responses and that this has an effect at both pre and post decisional stages. There are two main conclusions of this dissertation: firstly, emotion exerts a strong influence on perceptual and attentional processes but, at the same time, this influence may also be modulated by other factors internal and external to the individuals. Secondly, cognitive processes may modulate emotional prepotent responses, by serving a regulative function critical to driving and shaping human behavior in line with current goals.
La relazione tra emozione e cognizione è un argomento che ha suscitato grande interesse nella ricerca. Recentemente, una visione interattiva e di mutua influenza fra questi due processi è diventata predominante. Il presente lavoro di tesi indaga le influenze reciproche di emozione e cognizione, sia a livello comportamentale che neurale, in due specifici settori, quali l'attenzione e i processi decisionali. Nella prima parte, il lavoro presenta evidenze sperimentali di come le emozioni possano influenzare processi cognitivi come quelli percettivi ed attentivi. Allo stesso tempo aggiunge su come alcuni particolare fattori, come la personalità, le esigenze motivazionali del soggetto e il contesto sociale, possano modulare l’influenza che le emozioni esercitano sui processi cognitive in questione. Nella seconda parte é stato investigato l’influsso della cognizione sulle risposte emotive, in particolare durante i processi decisionali. I risultati degli esperimenti mostrano che regioni cerebrali cognitive, come la corteccia prefrontale dorsolaterale, sono implicate in modo causale nella regolazione e nel controllo di risposte emotive automatiche e che cio’ ha un effetto sia in fasi pre-decisionali (formazione della decisione) sia in fasi post-decisionali (cambiamento di preferenze). Due sono le principali conclusioni di questa tesi: in primo luogo, è stato mostrato che l'emozione esercita una forte influenza sui processi percettivi e attentivi, ma che, allo stesso tempo, questa influenza può essere modulata da altri fattori interni ed esterni agli individui. In secondo luogo, è stato mostrato che i processi cognitivi interagiscono con quelli emotivi svolgendo un funzione regolatrice fondamentale per guidare e plasmare il comportamento umano in linea con gli obiettivi correnti degli individui.

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24

Annella, Laura <1983&gt. "The future in action: neurophysiological and behavioral evidence of anticipatory motor simulation." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2012. http://amsdottorato.unibo.it/5081/1/Annella_Laura_Tesi.pdf.

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Abstract:

The motor system can no longer be considered as a mere passive executive system of motor commands generated elsewhere in the brain. On the contrary, it is deeply involved in perceptual and cognitive functions and acts as an “anticipation device”. The present thesis investigates the anticipatory motor mechanisms occurring in two particular instances: i) when processing sensory events occurring within the peripersonal space (PPS); and ii) when perceiving and predicting others’actions. The first study provides evidence that PPS representation in humans modulates neural activity within the motor system, while the second demonstrates that the motor mapping of sensory events occurring within the PPS critically relies on the activity of the premotor cortex. The third study provides direct evidence that the anticipatory motor simulation of others’ actions critically relies on the activity of the anterior node of the action observation network (AON), namely the inferior frontal cortex (IFC). The fourth study, sheds light on the pivotal role of the left IFC in predicting the future end state of observed right-hand actions. Finally, the fifth study examines how the ability to predict others’ actions could be influenced by a reduction of sensorimotor experience due to the traumatic or congenital loss of a limb. Overall, the present work provides new insights on: i) the anticipatory mechanisms of the basic reactivity of the motor system when processing sensory events occurring within the PPS, and the same anticipatory motor mechanisms when perceiving others’ implied actions; ii) the functional connectivity and plasticity of premotor-motor circuits both during the motor mapping of sensory events occurring within the PPS and when perceiving others’ actions; and iii) the anticipatory mechanisms related to others’ actions prediction.

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25

Annella, Laura <1983&gt. "The future in action: neurophysiological and behavioral evidence of anticipatory motor simulation." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2012. http://amsdottorato.unibo.it/5081/.

Full text

Abstract:

The motor system can no longer be considered as a mere passive executive system of motor commands generated elsewhere in the brain. On the contrary, it is deeply involved in perceptual and cognitive functions and acts as an “anticipation device”. The present thesis investigates the anticipatory motor mechanisms occurring in two particular instances: i) when processing sensory events occurring within the peripersonal space (PPS); and ii) when perceiving and predicting others’actions. The first study provides evidence that PPS representation in humans modulates neural activity within the motor system, while the second demonstrates that the motor mapping of sensory events occurring within the PPS critically relies on the activity of the premotor cortex. The third study provides direct evidence that the anticipatory motor simulation of others’ actions critically relies on the activity of the anterior node of the action observation network (AON), namely the inferior frontal cortex (IFC). The fourth study, sheds light on the pivotal role of the left IFC in predicting the future end state of observed right-hand actions. Finally, the fifth study examines how the ability to predict others’ actions could be influenced by a reduction of sensorimotor experience due to the traumatic or congenital loss of a limb. Overall, the present work provides new insights on: i) the anticipatory mechanisms of the basic reactivity of the motor system when processing sensory events occurring within the PPS, and the same anticipatory motor mechanisms when perceiving others’ implied actions; ii) the functional connectivity and plasticity of premotor-motor circuits both during the motor mapping of sensory events occurring within the PPS and when perceiving others’ actions; and iii) the anticipatory mechanisms related to others’ actions prediction.

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26

Sellitto, Manuela <1983&gt. "Functional and neural mechanisms of intertemporal choice." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2013. http://amsdottorato.unibo.it/5777/1/Sellitto_Manuela_tesi.pdf.

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People are daily faced with intertemporal choice, i.e., choices differing in the timing of their consequences, frequently preferring smaller-sooner rewards over larger-delayed ones, reflecting temporal discounting of the value of future outcomes. This dissertation addresses two main goals. New evidence about the neural bases of intertemporal choice is provided. Following the disruption of either the medial orbitofrontal cortex or the insula, the willingness to wait for larger-delayed outcomes is affected in odd directions, suggesting the causal involvement of these areas in regulating the value computation of rewards available with different timings. These findings were also supported by a reported imaging study. Moreover, this dissertation provides new evidence about how temporal discounting can be modulated at a behavioral level through different manipulations, e.g., allowing individuals to think about the distant time, pairing rewards with aversive events, or changing their perceived spatial position. A relationship between intertemporal choice, moral judgements and aging is also discussed. All these findings link together to support a unitary neural model of temporal discounting according to which signals coming from several cortical (i.e., medial orbitofrontal cortex, insula) and subcortical regions (i.e., amygdala, ventral striatum) are integrated to represent the subjective value of both earlier and later rewards, under the top-down regulation of dorsolateral prefrontal cortex. The present findings also support the idea that the process of outcome evaluation is strictly related to the ability to pre-experience and envision future events through self-projection, the anticipation of visceral feelings associated with receiving rewards, and the psychological distance from rewards. Furthermore, taking into account the emotions and the state of arousal at the time of decision seems necessary to understand impulsivity associated with preferring smaller-sooner goods in place of larger-later goods.

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27

Sellitto, Manuela <1983&gt. "Functional and neural mechanisms of intertemporal choice." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2013. http://amsdottorato.unibo.it/5777/.

Full text

Abstract:

People are daily faced with intertemporal choice, i.e., choices differing in the timing of their consequences, frequently preferring smaller-sooner rewards over larger-delayed ones, reflecting temporal discounting of the value of future outcomes. This dissertation addresses two main goals. New evidence about the neural bases of intertemporal choice is provided. Following the disruption of either the medial orbitofrontal cortex or the insula, the willingness to wait for larger-delayed outcomes is affected in odd directions, suggesting the causal involvement of these areas in regulating the value computation of rewards available with different timings. These findings were also supported by a reported imaging study. Moreover, this dissertation provides new evidence about how temporal discounting can be modulated at a behavioral level through different manipulations, e.g., allowing individuals to think about the distant time, pairing rewards with aversive events, or changing their perceived spatial position. A relationship between intertemporal choice, moral judgements and aging is also discussed. All these findings link together to support a unitary neural model of temporal discounting according to which signals coming from several cortical (i.e., medial orbitofrontal cortex, insula) and subcortical regions (i.e., amygdala, ventral striatum) are integrated to represent the subjective value of both earlier and later rewards, under the top-down regulation of dorsolateral prefrontal cortex. The present findings also support the idea that the process of outcome evaluation is strictly related to the ability to pre-experience and envision future events through self-projection, the anticipation of visceral feelings associated with receiving rewards, and the psychological distance from rewards. Furthermore, taking into account the emotions and the state of arousal at the time of decision seems necessary to understand impulsivity associated with preferring smaller-sooner goods in place of larger-later goods.

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28

Canzoneri, Elisa <1984&gt. "Plasticity in body and peripersonal space representations." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2013. http://amsdottorato.unibo.it/5895/1/CANZONERI_ELISA_TESI.pdf.

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Abstract:

A successful interaction with objects in the environment requires integrating information concerning object-location with the shape, dimension and position of body parts in space. The former information is coded in a multisensory representation of the space around the body, i.e. peripersonal space (PPS), whereas the latter is enabled by an online, constantly updated, action-orientated multisensory representation of the body (BR) that is critical for action. One of the critical features of these representations is that both PPS and BR are not fixed, but they dynamically change depending on different types of experience. In a series of experiment, I studied plastic properties of PPS and BR in humans. I have developed a series of methods to measure the boundaries of PPS representation (Chapter 4), to study its neural correlates (Chapter 3) and to assess BRs. These tasks have been used to study changes in PPS and BR following tool-use (Chapter 5), multisensory stimulation (Chapter 6), amputation and prosthesis implantation (Chapter 7) or social interaction (Chapter 8). I found that changes in the function (tool-use) and the structure (amputation and prosthesis implantation) of the physical body elongate or shrink both PPS and BR. Social context and social interaction also shape PPS representation. Such high degree of plasticity suggests that our sense of body in space is not given at once, but it is constantly constructed and adapted through experience.
Allo scopo di interagire con oggetti presenti nell’ambiente esterno è necessario integrare le informazioni sulla posizione degli oggetti nello spazio con informazioni riguardanti la forma, dimensione e posizione delle singole parti del corpo rispetto all’oggetto stesso. Due diverse rappresentazioni supportano la codifica di tali informazioni: da una parte, la rappresentazione dello Spazio Peripersonale, una rappresentazione multisensoriale dello spazio intorno al corpo, e dall’altra una rappresentazione multisensoriale del corpo, costantemente aggiornata e orientata all’azione. Una caratteristica critica di queste rappresentazioni è rappresentata dalle loro proprietà plastiche, cioè dalla possibilità di modificarsi in seguito a diversi tipi di esperienza. In questa tesi mi sono focalizzata sullo studio delle proprietà plastiche delle rappresentazioni del corpo e dello spazio peripersonale. Ho sviluppato una serie di metodi per valutare il confine dello spazio peripersonale (Capitolo 4), per studiare i suoi correlati neurali (Capitolo 3) e per valutare le rappresentazioni multisensoriali del corpo. Questi compiti sono stati usati per studiare modificazioni plastiche del corpo e dello spazio peripersonale in seguito all’utilizzo di uno strumento (Capitolo 5), in seguito a una stimolazione multisensoriale (Capitolo 6), amputazione e impianto di protesi (Capitolo 7) e nell’ambito delle interazioni sociali. I risultati ottenuti hanno mostrato come la modificazione nella funzione (in seguito all’utilizzo di uno strumento) o della struttura fisica (in seguito ad amputazione ed impianto di protesi) del corpo determinano una estensione o una contrazione sia della rappresentazione dello spazio peripersonale che della rappresentazione del corpo. Inoltre, i risultati ottenuti hanno dimostrato che la rappresentazione dello spazio peripersonale viene plasmata anche dalle interazioni sociali. Tale livello di plasticità suggerisce che l’esperienza del nostro corpo viene continuata costruita e aggiornata tramite le diverse esperienze.

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29

Canzoneri, Elisa <1984&gt. "Plasticity in body and peripersonal space representations." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2013. http://amsdottorato.unibo.it/5895/.

Full text

Abstract:

A successful interaction with objects in the environment requires integrating information concerning object-location with the shape, dimension and position of body parts in space. The former information is coded in a multisensory representation of the space around the body, i.e. peripersonal space (PPS), whereas the latter is enabled by an online, constantly updated, action-orientated multisensory representation of the body (BR) that is critical for action. One of the critical features of these representations is that both PPS and BR are not fixed, but they dynamically change depending on different types of experience. In a series of experiment, I studied plastic properties of PPS and BR in humans. I have developed a series of methods to measure the boundaries of PPS representation (Chapter 4), to study its neural correlates (Chapter 3) and to assess BRs. These tasks have been used to study changes in PPS and BR following tool-use (Chapter 5), multisensory stimulation (Chapter 6), amputation and prosthesis implantation (Chapter 7) or social interaction (Chapter 8). I found that changes in the function (tool-use) and the structure (amputation and prosthesis implantation) of the physical body elongate or shrink both PPS and BR. Social context and social interaction also shape PPS representation. Such high degree of plasticity suggests that our sense of body in space is not given at once, but it is constantly constructed and adapted through experience.
Allo scopo di interagire con oggetti presenti nell’ambiente esterno è necessario integrare le informazioni sulla posizione degli oggetti nello spazio con informazioni riguardanti la forma, dimensione e posizione delle singole parti del corpo rispetto all’oggetto stesso. Due diverse rappresentazioni supportano la codifica di tali informazioni: da una parte, la rappresentazione dello Spazio Peripersonale, una rappresentazione multisensoriale dello spazio intorno al corpo, e dall’altra una rappresentazione multisensoriale del corpo, costantemente aggiornata e orientata all’azione. Una caratteristica critica di queste rappresentazioni è rappresentata dalle loro proprietà plastiche, cioè dalla possibilità di modificarsi in seguito a diversi tipi di esperienza. In questa tesi mi sono focalizzata sullo studio delle proprietà plastiche delle rappresentazioni del corpo e dello spazio peripersonale. Ho sviluppato una serie di metodi per valutare il confine dello spazio peripersonale (Capitolo 4), per studiare i suoi correlati neurali (Capitolo 3) e per valutare le rappresentazioni multisensoriali del corpo. Questi compiti sono stati usati per studiare modificazioni plastiche del corpo e dello spazio peripersonale in seguito all’utilizzo di uno strumento (Capitolo 5), in seguito a una stimolazione multisensoriale (Capitolo 6), amputazione e impianto di protesi (Capitolo 7) e nell’ambito delle interazioni sociali. I risultati ottenuti hanno mostrato come la modificazione nella funzione (in seguito all’utilizzo di uno strumento) o della struttura fisica (in seguito ad amputazione ed impianto di protesi) del corpo determinano una estensione o una contrazione sia della rappresentazione dello spazio peripersonale che della rappresentazione del corpo. Inoltre, i risultati ottenuti hanno dimostrato che la rappresentazione dello spazio peripersonale viene plasmata anche dalle interazioni sociali. Tale livello di plasticità suggerisce che l’esperienza del nostro corpo viene continuata costruita e aggiornata tramite le diverse esperienze.

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30

Cecere, Roberto <1981&gt. "Residual visual processing following real or virtual lesions to primary visual pathways." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2013. http://amsdottorato.unibo.it/5896/1/Cecere_Roberto_tesi.pdf.

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Abstract:

Lesions to the primary geniculo-striate visual pathway cause blindness in the contralesional visual field. Nevertheless, previous studies have suggested that patients with visual field defects may still be able to implicitly process the affective valence of unseen emotional stimuli (affective blindsight) through alternative visual pathways bypassing the striate cortex. These alternative pathways may also allow exploitation of multisensory (audio-visual) integration mechanisms, such that auditory stimulation can enhance visual detection of stimuli which would otherwise be undetected when presented alone (crossmodal blindsight). The present dissertation investigated implicit emotional processing and multisensory integration when conscious visual processing is prevented by real or virtual lesions to the geniculo-striate pathway, in order to further clarify both the nature of these residual processes and the functional aspects of the underlying neural pathways. The present experimental evidence demonstrates that alternative subcortical visual pathways allow implicit processing of the emotional content of facial expressions in the absence of cortical processing. However, this residual ability is limited to fearful expressions. This finding suggests the existence of a subcortical system specialised in detecting danger signals based on coarse visual cues, therefore allowing the early recruitment of flight-or-fight behavioural responses even before conscious and detailed recognition of potential threats can take place. Moreover, the present dissertation extends the knowledge about crossmodal blindsight phenomena by showing that, unlike with visual detection, sound cannot crossmodally enhance visual orientation discrimination in the absence of functional striate cortex. This finding demonstrates, on the one hand, that the striate cortex plays a causative role in crossmodally enhancing visual orientation sensitivity and, on the other hand, that subcortical visual pathways bypassing the striate cortex, despite affording audio-visual integration processes leading to the improvement of simple visual abilities such as detection, cannot mediate multisensory enhancement of more complex visual functions, such as orientation discrimination.
Una lesione alla via visiva primaria (genicolo-striata) causa cecità nel campo visivo controlesionale. Ciononostante, studi precedenti suggeriscono che, mediante vie visive alternative che non coinvolgono la corteccia striata, i pazienti con deficit di campo visivo potrebbero ancora riuscire ad elaborare implicitamente la valenza affettiva degli stimoli emotivi non visti (affective blindsight) e di sfruttare meccanismi multisensoriali (audio-visivi), cosicchè la stimolazione uditiva migliori la detezione visiva di stimoli non percepiti quando presentati da soli (crossmodal blindsight). Nella presente tesi si sono indagate l’elaborazione emotiva implicita e l’integrazione multisensoriale osservabili quando l’elaborazione visiva cosciente è impedita da lesioni reali o virtuali della via genicolo-striata, in modo da chiarire sia la natura di tali processi sia gli aspetti funzionali dei circuiti neurali sottostanti. Le evidenze sperimentali qui presentate dimostrano che, in assenza di elaborazione corticale, le vie visive alternative sottocorticali consentono l’elaborazione implicita del contenuto emotivo delle espressioni facciali, ma che tale abilità è limitata alle espressioni di paura. Questo suggerisce l’esistenza di un sistema sottocorticale specializzato nella detezione di segnali di pericolo a partire da segnali visivi grezzi, permettendo dunque il rapido reclutamento di risposte comportamentali di lotta o fuga già prima che possa avvenire un riconoscimento conscio e dettagliato delle potenziali minacce. Inoltre, la presente tesi estende le conoscenze riguardo ai fenomeni di “crossmodal blindsight”, dimostrando che, a differenza della detezione visiva, la discriminazione di orientamento di linee non può essere migliorata dalla presentazione di suoni quando la corteccia striata non è funzionante. Questo dato suggerisce da un lato che la corteccia striata ha un ruolo causativo nel miglioramento “cross-modale” della sensibilità visiva all’orientamento e, dall’altro, che le vie visive sottocorticali che non coinvolgono la corteccia striata, anche se permettono l’integrazione di segnali audio-visivi e il miglioramento della semplice detezione, non possono potenziare abilità visive complesse, come la discriminazione di orientamento

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31

Cecere, Roberto <1981&gt. "Residual visual processing following real or virtual lesions to primary visual pathways." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2013. http://amsdottorato.unibo.it/5896/.

Full text

Abstract:

Lesions to the primary geniculo-striate visual pathway cause blindness in the contralesional visual field. Nevertheless, previous studies have suggested that patients with visual field defects may still be able to implicitly process the affective valence of unseen emotional stimuli (affective blindsight) through alternative visual pathways bypassing the striate cortex. These alternative pathways may also allow exploitation of multisensory (audio-visual) integration mechanisms, such that auditory stimulation can enhance visual detection of stimuli which would otherwise be undetected when presented alone (crossmodal blindsight). The present dissertation investigated implicit emotional processing and multisensory integration when conscious visual processing is prevented by real or virtual lesions to the geniculo-striate pathway, in order to further clarify both the nature of these residual processes and the functional aspects of the underlying neural pathways. The present experimental evidence demonstrates that alternative subcortical visual pathways allow implicit processing of the emotional content of facial expressions in the absence of cortical processing. However, this residual ability is limited to fearful expressions. This finding suggests the existence of a subcortical system specialised in detecting danger signals based on coarse visual cues, therefore allowing the early recruitment of flight-or-fight behavioural responses even before conscious and detailed recognition of potential threats can take place. Moreover, the present dissertation extends the knowledge about crossmodal blindsight phenomena by showing that, unlike with visual detection, sound cannot crossmodally enhance visual orientation discrimination in the absence of functional striate cortex. This finding demonstrates, on the one hand, that the striate cortex plays a causative role in crossmodally enhancing visual orientation sensitivity and, on the other hand, that subcortical visual pathways bypassing the striate cortex, despite affording audio-visual integration processes leading to the improvement of simple visual abilities such as detection, cannot mediate multisensory enhancement of more complex visual functions, such as orientation discrimination.
Una lesione alla via visiva primaria (genicolo-striata) causa cecità nel campo visivo controlesionale. Ciononostante, studi precedenti suggeriscono che, mediante vie visive alternative che non coinvolgono la corteccia striata, i pazienti con deficit di campo visivo potrebbero ancora riuscire ad elaborare implicitamente la valenza affettiva degli stimoli emotivi non visti (affective blindsight) e di sfruttare meccanismi multisensoriali (audio-visivi), cosicchè la stimolazione uditiva migliori la detezione visiva di stimoli non percepiti quando presentati da soli (crossmodal blindsight). Nella presente tesi si sono indagate l’elaborazione emotiva implicita e l’integrazione multisensoriale osservabili quando l’elaborazione visiva cosciente è impedita da lesioni reali o virtuali della via genicolo-striata, in modo da chiarire sia la natura di tali processi sia gli aspetti funzionali dei circuiti neurali sottostanti. Le evidenze sperimentali qui presentate dimostrano che, in assenza di elaborazione corticale, le vie visive alternative sottocorticali consentono l’elaborazione implicita del contenuto emotivo delle espressioni facciali, ma che tale abilità è limitata alle espressioni di paura. Questo suggerisce l’esistenza di un sistema sottocorticale specializzato nella detezione di segnali di pericolo a partire da segnali visivi grezzi, permettendo dunque il rapido reclutamento di risposte comportamentali di lotta o fuga già prima che possa avvenire un riconoscimento conscio e dettagliato delle potenziali minacce. Inoltre, la presente tesi estende le conoscenze riguardo ai fenomeni di “crossmodal blindsight”, dimostrando che, a differenza della detezione visiva, la discriminazione di orientamento di linee non può essere migliorata dalla presentazione di suoni quando la corteccia striata non è funzionante. Questo dato suggerisce da un lato che la corteccia striata ha un ruolo causativo nel miglioramento “cross-modale” della sensibilità visiva all’orientamento e, dall’altro, che le vie visive sottocorticali che non coinvolgono la corteccia striata, anche se permettono l’integrazione di segnali audio-visivi e il miglioramento della semplice detezione, non possono potenziare abilità visive complesse, come la discriminazione di orientamento

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32

Gessaroli, Erica <1983&gt. "Development, degeneration and neural network of the bodily self." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2014. http://amsdottorato.unibo.it/6342/1/Gessaroli_Erica_tesi.pdf.

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Abstract:

The question addressed by this dissertation is how the human brain builds a coherent representation of the body, and how this representation is used to recognize its own body. Recent approaches by neuroimaging and TMS revealed hints for a distinct brain representation of human body, as compared with other stimulus categories. Neuropsychological studies demonstrated that body-parts and self body-parts recognition are separate processes sub-served by two different, even if possibly overlapping, networks within the brain. Bodily self-recognition is one aspect of our ability to distinguish between self and others and the self/other distinction is a crucial aspect of social behaviour. This is the reason why I have conducted a series of experiment on subjects with everyday difficulties in social and emotional behaviour, such as patients with autism spectrum disorders (ASD) and patients with Parkinson’s disease (PD). More specifically, I studied the implicit self body/face recognition (Chapter 6) and the influence of emotional body postures on bodily self-processing in TD children as well as in ASD children (Chapter 7). I found that the bodily self-recognition is present in TD and in ASD children and that emotional body postures modulate self and others’ body processing. Subsequently, I compared implicit and explicit bodily self-recognition in a neuro-degenerative pathology, such as in PD patients, and I found a selective deficit in implicit but not in explicit self-recognition (Chapter 8). This finding suggests that implicit and explicit bodily self-recognition are separate processes subtended by different mechanisms that can be selectively impaired. If the bodily self is crucial for self/other distinction, the space around the body (personal space) represents the space of interaction and communication with others. When, I studied this space in autism, I found that personal space regulation is impaired in ASD children (Chapter 9).

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33

Gessaroli, Erica <1983&gt. "Development, degeneration and neural network of the bodily self." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2014. http://amsdottorato.unibo.it/6342/.

Full text

Abstract:

The question addressed by this dissertation is how the human brain builds a coherent representation of the body, and how this representation is used to recognize its own body. Recent approaches by neuroimaging and TMS revealed hints for a distinct brain representation of human body, as compared with other stimulus categories. Neuropsychological studies demonstrated that body-parts and self body-parts recognition are separate processes sub-served by two different, even if possibly overlapping, networks within the brain. Bodily self-recognition is one aspect of our ability to distinguish between self and others and the self/other distinction is a crucial aspect of social behaviour. This is the reason why I have conducted a series of experiment on subjects with everyday difficulties in social and emotional behaviour, such as patients with autism spectrum disorders (ASD) and patients with Parkinson’s disease (PD). More specifically, I studied the implicit self body/face recognition (Chapter 6) and the influence of emotional body postures on bodily self-processing in TD children as well as in ASD children (Chapter 7). I found that the bodily self-recognition is present in TD and in ASD children and that emotional body postures modulate self and others’ body processing. Subsequently, I compared implicit and explicit bodily self-recognition in a neuro-degenerative pathology, such as in PD patients, and I found a selective deficit in implicit but not in explicit self-recognition (Chapter 8). This finding suggests that implicit and explicit bodily self-recognition are separate processes subtended by different mechanisms that can be selectively impaired. If the bodily self is crucial for self/other distinction, the space around the body (personal space) represents the space of interaction and communication with others. When, I studied this space in autism, I found that personal space regulation is impaired in ASD children (Chapter 9).

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34

Scarpazza, Cristina <1985&gt. "Deficit in the Emotional Embodiment in Alexithymia." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2015. http://amsdottorato.unibo.it/6840/1/Scarpazza_Cristina_Tesi.pdf.

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Abstract:

Alexithymia refers to difficulties in recognizing one’s own emotions and others emotions. Theories of emotional embodiment suggest that, in order to understand other peoples’ feelings, observers re-experience, or simulate, the relevant component (i.e. somatic, motor, visceral) of emotion’s expressed by others in one’s self. In this way, the emotions are “embodied”. Critically, to date, there are no studies investigating the ability of alexithymic individuals in embodying the emotions conveyed by faces. In the present dissertation different implicit paradigms and techniques falling within the field of affective neuroscience have been employed in order to test a possible deficit in the embodiment of emotions in alexithymia while subjects were requested to observe faces manifesting different expression: fear, disgust, happiness and neutral. The level of the perceptual encoding of emotional faces and the embodiment of emotions in the somato-sensory and sensory-motor system have been investigated. Moreover, non-communicative motor reaction to emotional stimuli (i.e. visceral reactions) and interoceptive abilities of alexithymic subjects have been explored. The present dissertation provided convergent evidences in support of a deficit in the processing of fearful expression in subjects with high alexithymic personality traits. Indeed, the pattern of fear induced changes in the perceptual encoding, in the somato-sensory and in the somato-motor system (both the communicative and non communicative one) is widely and consistently altered in alexithymia. This support the hypothesis of a diminished responses to fearful stimuli in alexithymia. In addition, the overall results on happiness and disgust, although preliminary, provided interesting results. Indeed, the results on happiness revealed a defective perceptual encoding, coupled with a slight difficulty (i.e. delayed responses) at the level of the communicative somato-motor system, and the emotion of disgust has been found to be abnormally embodied at the level of the somato-sensory system.

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35

Scarpazza, Cristina <1985&gt. "Deficit in the Emotional Embodiment in Alexithymia." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2015. http://amsdottorato.unibo.it/6840/.

Full text

Abstract:

Alexithymia refers to difficulties in recognizing one’s own emotions and others emotions. Theories of emotional embodiment suggest that, in order to understand other peoples’ feelings, observers re-experience, or simulate, the relevant component (i.e. somatic, motor, visceral) of emotion’s expressed by others in one’s self. In this way, the emotions are “embodied”. Critically, to date, there are no studies investigating the ability of alexithymic individuals in embodying the emotions conveyed by faces. In the present dissertation different implicit paradigms and techniques falling within the field of affective neuroscience have been employed in order to test a possible deficit in the embodiment of emotions in alexithymia while subjects were requested to observe faces manifesting different expression: fear, disgust, happiness and neutral. The level of the perceptual encoding of emotional faces and the embodiment of emotions in the somato-sensory and sensory-motor system have been investigated. Moreover, non-communicative motor reaction to emotional stimuli (i.e. visceral reactions) and interoceptive abilities of alexithymic subjects have been explored. The present dissertation provided convergent evidences in support of a deficit in the processing of fearful expression in subjects with high alexithymic personality traits. Indeed, the pattern of fear induced changes in the perceptual encoding, in the somato-sensory and in the somato-motor system (both the communicative and non communicative one) is widely and consistently altered in alexithymia. This support the hypothesis of a diminished responses to fearful stimuli in alexithymia. In addition, the overall results on happiness and disgust, although preliminary, provided interesting results. Indeed, the results on happiness revealed a defective perceptual encoding, coupled with a slight difficulty (i.e. delayed responses) at the level of the communicative somato-motor system, and the emotion of disgust has been found to be abnormally embodied at the level of the somato-sensory system.

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36

Beck, Brianna <1985&gt. "Visual-somatosensory interactions in mental representations of the body and the face." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2015. http://amsdottorato.unibo.it/6848/1/beck_brianna_tesi.pdf.

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The body is represented in the brain at levels that incorporate multisensory information. This thesis focused on interactions between vision and cutaneous sensations (i.e., touch and pain). Experiment 1 revealed that there are partially dissociable pathways for visual enhancement of touch (VET) depending upon whether one sees one’s own body or the body of another person. This indicates that VET, a seeming low-level effect on spatial tactile acuity, is actually sensitive to body identity. Experiments 2-4 explored the effect of viewing one’s own body on pain perception. They demonstrated that viewing the body biases pain intensity judgments irrespective of actual stimulus intensity, and, more importantly, reduces the discriminative capacities of the nociceptive pathway encoding noxious stimulus intensity. The latter effect only occurs if the pain-inducing event itself is not visible, suggesting that viewing the body alone and viewing a stimulus event on the body have distinct effects on cutaneous sensations. Experiment 5 replicated an enhancement of visual remapping of touch (VRT) when viewing fearful human faces being touched, and further demonstrated that VRT does not occur for observed touch on non-human faces, even fearful ones. This suggests that the facial expressions of non-human animals may not be simulated within the somatosensory system of the human observer in the same way that the facial expressions of other humans are. Finally, Experiment 6 examined the enfacement illusion, in which synchronous visuo-tactile inputs cause another’s face to be assimilated into the mental self-face representation. The strength of enfacement was not affected by the other’s facial expression, supporting an asymmetric relationship between processing of facial identity and facial expressions. Together, these studies indicate that multisensory representations of the body in the brain link low-level perceptual processes with the perception of emotional cues and body/face identity, and interact in complex ways depending upon contextual factors.

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37

Beck, Brianna <1985&gt. "Visual-somatosensory interactions in mental representations of the body and the face." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2015. http://amsdottorato.unibo.it/6848/.

Full text

Abstract:

The body is represented in the brain at levels that incorporate multisensory information. This thesis focused on interactions between vision and cutaneous sensations (i.e., touch and pain). Experiment 1 revealed that there are partially dissociable pathways for visual enhancement of touch (VET) depending upon whether one sees one’s own body or the body of another person. This indicates that VET, a seeming low-level effect on spatial tactile acuity, is actually sensitive to body identity. Experiments 2-4 explored the effect of viewing one’s own body on pain perception. They demonstrated that viewing the body biases pain intensity judgments irrespective of actual stimulus intensity, and, more importantly, reduces the discriminative capacities of the nociceptive pathway encoding noxious stimulus intensity. The latter effect only occurs if the pain-inducing event itself is not visible, suggesting that viewing the body alone and viewing a stimulus event on the body have distinct effects on cutaneous sensations. Experiment 5 replicated an enhancement of visual remapping of touch (VRT) when viewing fearful human faces being touched, and further demonstrated that VRT does not occur for observed touch on non-human faces, even fearful ones. This suggests that the facial expressions of non-human animals may not be simulated within the somatosensory system of the human observer in the same way that the facial expressions of other humans are. Finally, Experiment 6 examined the enfacement illusion, in which synchronous visuo-tactile inputs cause another’s face to be assimilated into the mental self-face representation. The strength of enfacement was not affected by the other’s facial expression, supporting an asymmetric relationship between processing of facial identity and facial expressions. Together, these studies indicate that multisensory representations of the body in the brain link low-level perceptual processes with the perception of emotional cues and body/face identity, and interact in complex ways depending upon contextual factors.

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38

Dundon, Neil Michael <1984&gt. "Residual function, spontaneous reorganisation and treatment plasticity in homonymous visual field defects." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2015. http://amsdottorato.unibo.it/6872/1/neil_dundon_tesi.pdf.

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Abstract:

This thesis will focus on the residual function and visual and attentional deficits in human patients, which accompany damage to the visual cortex or its thalamic afferents, and plastic changes, which follow it. In particular, I will focus on homonymous visual field defects, which comprise a broad set of central disorders of vision. I will present experimental evidence that when the primary visual pathway is completely damaged, the only signal that can be implicitly processed via subcortical visual networks is fear. I will also present data showing that in a patient with relative deafferentation of visual cortex, changes in the spatial tuning and response gain of the contralesional and ipsilesional cortex are observed, which are accompanied by changes in functional connectivity with regions belonging to the dorsal attentional network and the default mode network. I will also discuss how cortical plasticity might be harnessed to improve recovery through novel treatments. Moreover, I will show how treatment interventions aimed at recruiting spared subcortical pathway supporting multisensory orienting can drive network level change.

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39

Dundon, Neil Michael <1984&gt. "Residual function, spontaneous reorganisation and treatment plasticity in homonymous visual field defects." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2015. http://amsdottorato.unibo.it/6872/.

Full text

Abstract:

This thesis will focus on the residual function and visual and attentional deficits in human patients, which accompany damage to the visual cortex or its thalamic afferents, and plastic changes, which follow it. In particular, I will focus on homonymous visual field defects, which comprise a broad set of central disorders of vision. I will present experimental evidence that when the primary visual pathway is completely damaged, the only signal that can be implicitly processed via subcortical visual networks is fear. I will also present data showing that in a patient with relative deafferentation of visual cortex, changes in the spatial tuning and response gain of the contralesional and ipsilesional cortex are observed, which are accompanied by changes in functional connectivity with regions belonging to the dorsal attentional network and the default mode network. I will also discuss how cortical plasticity might be harnessed to improve recovery through novel treatments. Moreover, I will show how treatment interventions aimed at recruiting spared subcortical pathway supporting multisensory orienting can drive network level change.

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40

Candini, Michela <1986&gt. "The Contribution of Visual and Acoustic Information to Bodily Self Recognition." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2016. http://amsdottorato.unibo.it/7394/1/Candini_Michela_tesi.pdf.

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Abstract:

One of the most intriguing topic addressed by researchers across the cognitive sciences concerns the “self” and the self-other distinction. The present thesis adds to this debate by exploring the recognition of bodily self, based on visual and acoustical information. The first part of the present dissertation focuses on mechanisms and neural bases of bodily self, adopting a classical neuropsychological approach. Brain damaged patients were submitted to two different tasks designed for testing implicit and explicit self-body recognition using pictures depicting left and right hands as stimuli that belong to the participant or to other people. In Study 1, right and left brain damaged patients’ performance was compared to verify whether implicit and explicit self-body recognition are mediated by different cerebral networks that can be selectively impaired after focal brain lesion. A Voxel-based lesion-symptom mapping analysis revealed that an integrated cortical–subcortical right frontal (motor) network is crucial for an implicit knowledge of one’s own body. Conversely, both hemispheres contribute to an explicit knowledge of our body. In addition, Study 2 demonstrates how the implicit and explicit bodily knowledge is selectively impaired in patients with and without pathological embodiment of others’ body. The second part of the thesis explores the contribution of voice to self/other distinction. In Study 3, implicit and explicit self-voice recognition was investigated in healthy individuals. Interestingly, self-voice was better processed when an implicit rather than an explicit recognition was required. Finally, in Study 4, the anatomical basis of implicit and explicit self-voice recognition was investigated in neuropsychological patients. Behavioural and anatomical data demonstrates the involvement of right hemisphere in implicit processing and the joint contribution of both hemispheres in explicit recognition of self-voice. Overall, this thesis highlights the role played by visual and acoustic cues in building the sense of body-ownership.

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41

Candini, Michela <1986&gt. "The Contribution of Visual and Acoustic Information to Bodily Self Recognition." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2016. http://amsdottorato.unibo.it/7394/.

Full text

Abstract:

One of the most intriguing topic addressed by researchers across the cognitive sciences concerns the “self” and the self-other distinction. The present thesis adds to this debate by exploring the recognition of bodily self, based on visual and acoustical information. The first part of the present dissertation focuses on mechanisms and neural bases of bodily self, adopting a classical neuropsychological approach. Brain damaged patients were submitted to two different tasks designed for testing implicit and explicit self-body recognition using pictures depicting left and right hands as stimuli that belong to the participant or to other people. In Study 1, right and left brain damaged patients’ performance was compared to verify whether implicit and explicit self-body recognition are mediated by different cerebral networks that can be selectively impaired after focal brain lesion. A Voxel-based lesion-symptom mapping analysis revealed that an integrated cortical–subcortical right frontal (motor) network is crucial for an implicit knowledge of one’s own body. Conversely, both hemispheres contribute to an explicit knowledge of our body. In addition, Study 2 demonstrates how the implicit and explicit bodily knowledge is selectively impaired in patients with and without pathological embodiment of others’ body. The second part of the thesis explores the contribution of voice to self/other distinction. In Study 3, implicit and explicit self-voice recognition was investigated in healthy individuals. Interestingly, self-voice was better processed when an implicit rather than an explicit recognition was required. Finally, in Study 4, the anatomical basis of implicit and explicit self-voice recognition was investigated in neuropsychological patients. Behavioural and anatomical data demonstrates the involvement of right hemisphere in implicit processing and the joint contribution of both hemispheres in explicit recognition of self-voice. Overall, this thesis highlights the role played by visual and acoustic cues in building the sense of body-ownership.

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42

Borhani, Khatereh <1985&gt. "Sensory and somatosensory underpinnings of emotion processing." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2016. http://amsdottorato.unibo.it/7592/1/Borhani_Khatereh_tesi.pdf.

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Alexithymia is characterized by difficulties in recognizing one’s own emotions and others’ emotions, specially fear. Recognizing emotions is associated with remarkable changes in somatosensory and sensory (particularly visual) processing. For instance theories about emotion processing suggest a strong association between emotion processing and somatic markers. The aim of the present thesis is to assess whether the difficulties in emotion processing shown by alexitimic subjects can affect somatosensory and sensory (especially visual) processing. To this end different somatosensory modalities (e.g. temperature, pain, tactile, touch, etc) and visual stimuli (e.g. face and body expressions) were used to compare the somatosensory and sensory processing in people with high and low scores of alexithymia. These experiments provided evidence that emotional processing deficit seems to be related to the alterations in somatosensory processing (Experiments 1, and 2), in visual processing, early visual encoding (Experiments 3, 4, and 6), and in physiological reactivity, particularly visceral reactivity (Experiment 5), which prevents these individuals to correctly perceive emotions. Together, these studies suggest that the emotional difficulties in alexithymia might be grounded in the specific low-level somatosensory system. Moreover, the lack of emotional modulation at the early stage of visual processing indicates that the rapid modulation of the amygdala over the visual cortices may be reduced, thus suggesting a hyporeactivity of the amygdala in individual with high levels of alexithymia.

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43

Garofalo, Sara <1986&gt. "Adaptive and Maladaptive Implications of Reinforcement Learning Processes: Fronto-Striatal Loops and Behavioural Correlates." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2016. http://amsdottorato.unibo.it/7596/1/Garofalo_Sara_tesi.pdf.

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That humans and animals learn from interaction with the environment is a foundational idea underlying nearly all theories of learning and intelligence. Learning that certain outcomes are associated with specific actions or stimuli (both internal and external), is at the very core of the capacity to adapt behaviour to environmental changes. In the present work, appetitive and aversive reinforcement learning paradigms have been used to investigate the fronto-striatal loops and behavioural correlates of adaptive and maladaptive reinforcement learning processes, aiming to a deeper understanding of how cortical and subcortical substrates interacts between them and with other brain systems to support learning. By combining a large variety of neuroscientific approaches, including behavioral and psychophysiological methods, EEG and neuroimaging techniques, these studies aim at clarifying and advancing the knowledge of the neural bases and computational mechanisms of reinforcement learning, both in normal and neurologically impaired population.

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44

Garofalo, Sara <1986&gt. "Adaptive and Maladaptive Implications of Reinforcement Learning Processes: Fronto-Striatal Loops and Behavioural Correlates." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2016. http://amsdottorato.unibo.it/7596/.

Full text

Abstract:

That humans and animals learn from interaction with the environment is a foundational idea underlying nearly all theories of learning and intelligence. Learning that certain outcomes are associated with specific actions or stimuli (both internal and external), is at the very core of the capacity to adapt behaviour to environmental changes. In the present work, appetitive and aversive reinforcement learning paradigms have been used to investigate the fronto-striatal loops and behavioural correlates of adaptive and maladaptive reinforcement learning processes, aiming to a deeper understanding of how cortical and subcortical substrates interacts between them and with other brain systems to support learning. By combining a large variety of neuroscientific approaches, including behavioral and psychophysiological methods, EEG and neuroimaging techniques, these studies aim at clarifying and advancing the knowledge of the neural bases and computational mechanisms of reinforcement learning, both in normal and neurologically impaired population.

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45

Bertossi, Elena <1984&gt. "The Role of Ventromedial Prefrontal Cortex in Mental Time Travel and Mind Wandering." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2016. http://amsdottorato.unibo.it/7623/1/Bertossi_Elena_Tesi.pdf.

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Recent research showed that a network of brain regions known as the Default Mode Network (DMN), including the ventromedial prefrontal cortex (vmPFC), is active when individuals remember the past, imagine the future, take the perspective of others, as well as during spontaneous cognition (mind wandering). The goal of this dissertation is to investigate whether the vmPFC plays a crucial role during DMN-related cognitive processes, such as MTT and mind wandering. Experiment 1 revealed that a damage to the vmPFC provokes the disruption of past and future MTT and a decreased ability to imagine future other-related episodes. vmPFC role extends to imagining events that are not self-relevant indicating that vmPFC is crucial for the imagination of complex experiences alternative to the current reality. In experiment 2, findings showed that a lesion to vmPFC disrupts the ability to construct complex atemporal scenarios. However, unlike the control groups, vmPFC patients had more difficulties in imagining future compared to fictitious experiences, suggesting that vmPFC is more critical for the simulation of future episodes. Experiment 3 revealed that these results are not explained by the disruption of non-episodic capabilities, such as narrative and working memory abilities. Furthermore, experiment 4 explored the effect of a lesion to vmPFC on the occurrence of mind wandering. A damage to the vmPFC provokes a decreased propensity to mind-wander, showing that vmPFC supports spontaneous cognition. Experiment 5 confirmed the involvement of the medial prefrontal cortex (mPFC) in supporting mind wandering. Using the transcranial direct current stimulation to inhibit the mPFC we could decrease the intensity of mind wandering in males. Together, these results point out the fundamental role of vmPFC in allowing human beings to escape the here and now, whether it occurs deliberately or spontaneously.

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Paracampo, Riccardo <1986&gt. "Sensorimotor Network in Social Cognition." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2017. http://amsdottorato.unibo.it/7878/1/ParacampoRiccardo_SensorimotorNetworkSocialCognition.pdf.

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Our motor and somatosensory cortices originally evolved to control our movement through the environment. In the past decade, one of the most exciting developments in cognitive neuroscience is the discovery that the same sensorimotor brain regions that are used to control our body are involved in the perception of others’ actions, sensations and emotions. Human beings are equipped with a mechanism mapping perceptual representations of actions, sensations, and emotions onto sensorimotor representations, thus, perception of others might be inherently grounded in the same brain regions involved in first-hand subjective experiences. While the notion that observing, or imagining actions, emotions, and sensations in others triggers vicarious activations in the sensorimotor network is widely accepted, evidence about the specific role of these activations in social cognition is meagre and still largely based on correlational data. The experiments included in the present thesis aim at exploring the functional role of the sensorimotor network in understanding others’ internal emotional and cognitive states. We used neuromodulation tools to interfere with brain activity in regions involved in moving and sensing the body while participants were asked to understand others’ emotions or intentions. In experiment 1 to 7 we focused on the ability to accurately understand amusement from observed smiles, while in experiment 8 to 10 we explored the ability to rate the pain felt by another individual when her/his experience is described only through text. Our results show that interference with activity within somatosensory and motor cortices impairs participants’ ability to understand others’ emotions. Combining complex naturalistic tasks to neuromodulation tools, the present thesis sheds novel light on the behavioural relevance of vicarious activations in the sensorimotor network, by establishing a strong and direct causal link between sensorimotor brain networks and others’ understanding that was only suggested in the past.

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Grasso, Paolo Antonino <1986&gt. "The Role of the Subcortical Dorsal Visual Pathway in the Recovery of Visual Field Defects." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2017. http://amsdottorato.unibo.it/8095/1/Grasso_Paolo_tesi.pdf.

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Lateralized post-chiasmatic lesions to the primary visual pathway result in loss of vision over the visual field retinotopically corresponding to the site of the lesion. Previous studies showed that a systematic audio-visual training could constitute an efficient tool for the rehabilitation of such disturbances as revealed by ameliorated clinical performances in various visual domains. The first part of the present dissertation aim to shed light on the substrates underlying multisensory mediated recovery of visual field defects. Experiment 1 and Experiment 2, demonstrated that a sustained audio-visual training can promote stable plastic neural changes within the cortex, likely reflecting an enhanced activity of those neural circuits connecting superior colliculus to cortical areas within the dorsal stream. The second part of the present dissertation aimed to shed light on the functionality and the characteristics of extrageniculate circuits targeting extrastriate visual areas within the dorsal stream. Experiment 3 and Experiment 4, suggested that these connections remain responsive even when a lesion prevents visual processing within the primary visual channel and that these connections could play a relevant role in the rapid processing of salient visual stimuli. Overall, the present experimental evidence suggest that visual processing depends on a variety of neural circuits and that a lesion to the primary visual pathway do not abolish the visual processing mediated by alternative routes. Moreover, activity within these routes could be exploited in a rehabilitative perspective, as revealed by ameliorated clinical performances and stable plastic neural changes induced by a systematic multisensory audio-visual training in hemianopic patients.

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Cataldo, Antonio <1987&gt. "Integration of Multiple Simultaneous Stimuli within and between Somatosensory sub-Modalities." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2017. http://amsdottorato.unibo.it/8164/1/Cataldo_PhDThesis_13042017.pdf.

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Psychological characterisation of the somatosensory system often focusses on minimal units of perception, such as detection, localisation, and magnitude estimation of single events. Research on how multiple simultaneous stimuli are aggregated to create integrated, synthetic experiences is rarer. This thesis aims to shed a light on the mechanisms underlying the integration of multiple simultaneous stimuli, within and between different sub-modalities of the somatosensory system. First, we investigated the ability of healthy individuals to perceive the total intensity of composite somatosensory patterns. We found that the overall intensity of tactile, cold, or warm patterns was systematically overestimated when the multiple simultaneous stimuli had different intensities. Perception of somatosensory totals was biased towards the most salient element in the pattern. Furthermore, we demonstrated that peak-biased aggregation is a genuine perceptual phenomenon which does not rely on the discrimination of the parts, but is rather based on the salience of each stimulus. Next, we studied a classical thermal illusion to assess participants’ ability to localise thermal stimuli delivered on the fingers either in isolation, or in uniform and non-uniform patterns. We found that despite a surprisingly high accuracy in reporting the location of a single stimulus, when participants were presented with non-uniform patterns, their ability to identify the thermal state of a specific finger was completely abolished. Lastly, we investigated the perceptual and neural correlates of thermo-nociceptive interaction during the presentation of multiple thermal stimuli. We found that inhibition of pain by warmth was independent from both the position and the number of thermal stimuli administered. Our results suggest that nonlinear integration of multiple stimuli, within and between somatosensory sub-modalities, may be an efficient way by which the somatosensory system synthesises the complexity of reality, providing an extended and coherent perception of the world, in spite of its deep bandwidth limitations.

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Starita, Francesca <1989&gt. "Alexithymia as impairment in constructing the internal representation of emotional stimuli." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2018. http://amsdottorato.unibo.it/8349/1/Starita%20tesi.pdf.

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Alexithymia is a personality trait characterized by difficulties in processing emotional stimuli. Here, Experiment1 shows that alexithymia has a significant impact on everyday life, being related to lower emotional intelligence, empathy and wellbeing. Experiment2 shows that alexithymia is related to the need for more emotional intensity to identify fear in facial expressions. Although these experiments contribute to the literature describing the difficulties of alexithymia, the basic mechanisms underlying such difficulties remain poorly understood. For this reason, the remaining of this thesis focuses on investigating whether differences in emotional learning may characterize alexithymia. Indeed, through emotional learning the internal representation of stimuli is shaped, so that neutral stimuli acquire emotional value. Impairment in this process has been reported in clinical conditions marked by difficulties in emotion processing; nevertheless, this has never been investigated in alexithymia. Given this, Experiment3 shows that alexithymia is related to impairment in learning the aversive value of stimuli, evidenced by reduced physiological markers of emotional prediction in Pavlovian threat conditioning. On the contrary, Experiment4 did not find such evidence, when learning appetitive value. Nevertheless, evidence for impairment in learning the appetitive value of stimuli was found in Experiment5, where electrophysiological markers of prediction and prediction error were assessed during Pavlovian reward conditioning. Finally, Experiment 6 examined the ability to learn the emotional value of actions during instrumental learning, and to use this learned value for adaptive behavior in a new context. Here, alexithymia was related to a difficulty in learning from punishment, marked by longer response time when having to avoid stimuli, which had previously acquired aversive value, encountered in a new context. Together, these results indicate impairment in emotional learning in alexithymia, which may be more severe for aversive than appetitive stimuli. The new insight provided by these results for the understanding of alexithymia is discussed.

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Piserchia, Valentina <1973&gt. "Encoding of visual targets during 3D reaching movements in human and non-human primates." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2018. http://amsdottorato.unibo.it/8407/1/Tesi%20di%20Dottorato_Valentina%20Piserchia.pdf.

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The aim of my thesis was to investigate how reaching for visual targets placed in 3D space influences the coordinate frames and the kinematics in non-human and human primates. To this end, I conducted three studies. The first study was conducted on non-human primates to find the predominant reference frame of cells in a specific reach related area of the PPC (area PEc) while reaching towards targets placed at different depths and directions; we tested whether PEc reaching cells displayed hand- and/or body-centered coding of reach targets. We found that the majority of PEc neurons encoded targets in a mixed body/hand-centered reference frame. Our findings highlight a role for area PEc as intermediate node between the visually dominated area V6A and the somatosensory dominated area PE. The second study was conducted on healthy human subjects to find the reference frame used while reaching towards targets placed at different depths and directions. Our results revealed reach error patterns based on both eye- and space-centered coordinate systems: in depth more biased towards a space-centered representation and in direction mixed between space- and eye-centered representation. The third study was conducted on a patient with a parietal cortex lesion who showed optic ataxia symptoms. Optic ataxia patients show deficits in visuo-manual guidance especially when reaching to targets located in the periphery of the visual field. By manipulating gaze position and hand position of visual reaching targets, placed at different depth and directions, we investigated how reaching in peripheral and central viewing conditions influenced the trajectories and reach errors of the patient and controls. Our results suggest that the reaching inaccuracies observed, in particular in the configurations where the direction of gaze and reach differed, are due to a disruption of the online correction mechanism and that the PPC is involved in these automatic corrections.

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Dissertations / Theses on the topic 'M-PSI/02'

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